# Valtrinity

> Valtrinity is a UK site of single-purpose online tools: calculators, unit and number converters, text and writing tools, PDF and image tools, developer utilities, SEO checks and web security checks. Each tool has its own page, works straight away and needs no account for most uses.

Prices and allowances: most tools have no daily limit. Lookups that call our servers are limited to 5 a day without an account and 10 with one. Passes, packs and the Unlimited plan are listed at https://valtrinity.com/pricing/.

AI agents can call some tools directly through our MCP server at https://valtrinity.com/api/mcp (Streamable HTTP, no sign in, 20 tool calls a day per address).

## Unit Converters

- [Unit Converters](https://valtrinity.com/converters/): Convert length, weight, volume, temperature, speed, area, data and more, plus number bases such as binary and hex, colour codes and sizes.
- [Centimetres to Inches Converter](https://valtrinity.com/tools/cm-to-inches/): Convert centimetres to inches (cm to in) with the formula and a quick table.
- [Inches to Centimetres Converter](https://valtrinity.com/tools/inches-to-cm/): Convert inches to centimetres (in to cm) with the formula and a quick table.
- [Millimetres to Inches Converter](https://valtrinity.com/tools/mm-to-inches/): Convert millimetres to inches (mm to in) with the formula and a quick table.
- [Inches to Millimetres Converter](https://valtrinity.com/tools/inches-to-mm/): Convert inches to millimetres (in to mm) with the formula and a quick table.
- [Metres to Feet Converter](https://valtrinity.com/tools/metres-to-feet/): Convert metres to feet (m to ft) with the formula and a quick table.
- [Feet to Metres Converter](https://valtrinity.com/tools/feet-to-metres/): Convert feet to metres (ft to m) with the formula and a quick table.
- [Kilometres to Miles Converter](https://valtrinity.com/tools/km-to-miles/): Convert kilometres to miles (km to mi) with the formula and a quick table.
- [Miles to Kilometres Converter](https://valtrinity.com/tools/miles-to-km/): Convert miles to kilometres (mi to km) with the formula and a quick table.
- [Metres to Yards Converter](https://valtrinity.com/tools/metres-to-yards/): Convert metres to yards (m to yd) with the formula and a quick table.
- [Yards to Metres Converter](https://valtrinity.com/tools/yards-to-metres/): Convert yards to metres (yd to m) with the formula and a quick table.
- [Centimetres to Feet Converter](https://valtrinity.com/tools/cm-to-feet/): Convert centimetres to feet (cm to ft) with the formula and a quick table.
- [Feet to Centimetres Converter](https://valtrinity.com/tools/feet-to-cm/): Convert feet to centimetres (ft to cm) with the formula and a quick table.
- [Inches to Feet Converter](https://valtrinity.com/tools/inches-to-feet/): Convert inches to feet (in to ft) with the formula and a quick table.
- [Feet to Inches Converter](https://valtrinity.com/tools/feet-to-inches/): Convert feet to inches (ft to in) with the formula and a quick table.
- [Feet and Inches to Centimetres Converter](https://valtrinity.com/tools/feet-and-inches-to-cm/): Convert feet and inches to centimetres (ft in to cm) with the formula and a quick table.
- [Centimetres to Feet and Inches Converter](https://valtrinity.com/tools/cm-to-feet-and-inches/): Convert centimetres to feet and inches (cm to ft in) with the formula and a quick table.
- [Feet and Inches to Metres Converter](https://valtrinity.com/tools/feet-and-inches-to-metres/): Convert feet and inches to metres (ft in to m) with the formula and a quick table.
- [Metres to Feet and Inches Converter](https://valtrinity.com/tools/metres-to-feet-and-inches/): Convert metres to feet and inches (m to ft in) with the formula and a quick table.
- [Nautical Miles to Kilometres Converter](https://valtrinity.com/tools/nautical-miles-to-km/): Convert nautical miles to kilometres (nmi to km) with the formula and a quick table.
- [Kilometres to Nautical Miles Converter](https://valtrinity.com/tools/km-to-nautical-miles/): Convert kilometres to nautical miles (km to nmi) with the formula and a quick table.
- [Kilograms to Pounds Converter](https://valtrinity.com/tools/kg-to-pounds/): Convert kilograms to pounds (kg to lb) with the formula and a quick table.
- [Pounds to Kilograms Converter](https://valtrinity.com/tools/pounds-to-kg/): Convert pounds to kilograms (lb to kg) with the formula and a quick table.
- [Grams to Ounces Converter](https://valtrinity.com/tools/grams-to-ounces/): Convert grams to ounces (g to oz) with the formula and a quick table.
- [Ounces to Grams Converter](https://valtrinity.com/tools/ounces-to-grams/): Convert ounces to grams (oz to g) with the formula and a quick table.
- [Kilograms to Stones Converter](https://valtrinity.com/tools/kg-to-stones/): Convert kilograms to stones (kg to st) with the formula and a quick table.
- [Stones to Kilograms Converter](https://valtrinity.com/tools/stones-to-kg/): Convert stones to kilograms (st to kg) with the formula and a quick table.
- [Stones to Pounds Converter](https://valtrinity.com/tools/stones-to-pounds/): Convert stones to pounds (st to lb) with the formula and a quick table.
- [Pounds to Stones Converter](https://valtrinity.com/tools/pounds-to-stones/): Convert pounds to stones (lb to st) with the formula and a quick table.
- [Stones and Pounds to Kilograms Converter](https://valtrinity.com/tools/stones-and-pounds-to-kg/): Convert stones and pounds to kilograms (st lb to kg) with the formula and a quick table.
- [Kilograms to Stones and Pounds Converter](https://valtrinity.com/tools/kg-to-stones-and-pounds/): Convert kilograms to stones and pounds (kg to st lb) with the formula and a quick table.
- [Ounces to Pounds Converter](https://valtrinity.com/tools/ounces-to-pounds/): Convert ounces to pounds (oz to lb) with the formula and a quick table.
- [Pounds to Ounces Converter](https://valtrinity.com/tools/pounds-to-ounces/): Convert pounds to ounces (lb to oz) with the formula and a quick table.
- [Litres to UK Gallons Converter](https://valtrinity.com/tools/litres-to-uk-gallons/): Convert litres to UK gallons (L to UK gal) with the formula and a quick table.
- [UK Gallons to Litres Converter](https://valtrinity.com/tools/uk-gallons-to-litres/): Convert UK gallons to litres (UK gal to L) with the formula and a quick table.
- [Litres to US Gallons Converter](https://valtrinity.com/tools/litres-to-us-gallons/): Convert litres to US gallons (L to US gal) with the formula and a quick table.
- [US Gallons to Litres Converter](https://valtrinity.com/tools/us-gallons-to-litres/): Convert US gallons to litres (US gal to L) with the formula and a quick table.
- [Millilitres to UK Fluid Ounces Converter](https://valtrinity.com/tools/ml-to-uk-fluid-ounces/): Convert millilitres to UK fluid ounces (ml to UK fl oz) with the formula and a quick table.
- [UK Fluid Ounces to Millilitres Converter](https://valtrinity.com/tools/uk-fluid-ounces-to-ml/): Convert UK fluid ounces to millilitres (UK fl oz to ml) with the formula and a quick table.
- [Millilitres to US Fluid Ounces Converter](https://valtrinity.com/tools/ml-to-us-fluid-ounces/): Convert millilitres to US fluid ounces (ml to US fl oz) with the formula and a quick table.
- [US Fluid Ounces to Millilitres Converter](https://valtrinity.com/tools/us-fluid-ounces-to-ml/): Convert US fluid ounces to millilitres (US fl oz to ml) with the formula and a quick table.
- [Litres to UK Pints Converter](https://valtrinity.com/tools/litres-to-uk-pints/): Convert litres to UK pints (L to UK pt) with the formula and a quick table.
- [UK Pints to Litres Converter](https://valtrinity.com/tools/uk-pints-to-litres/): Convert UK pints to litres (UK pt to L) with the formula and a quick table.
- [UK Gallons to US Gallons Converter](https://valtrinity.com/tools/uk-gallons-to-us-gallons/): Convert UK gallons to US gallons (UK gal to US gal) with the formula and a quick table.
- [US Gallons to UK Gallons Converter](https://valtrinity.com/tools/us-gallons-to-uk-gallons/): Convert US gallons to UK gallons (US gal to UK gal) with the formula and a quick table.
- [Cubic Metres to Litres Converter](https://valtrinity.com/tools/cubic-metres-to-litres/): Convert cubic metres to litres (m³ to L) with the formula and a quick table.
- [Litres to Cubic Metres Converter](https://valtrinity.com/tools/litres-to-cubic-metres/): Convert litres to cubic metres (L to m³) with the formula and a quick table.
- [Square Metres to Square Feet Converter](https://valtrinity.com/tools/square-metres-to-square-feet/): Convert square metres to square feet (m² to ft²) with the formula and a quick table.
- [Square Feet to Square Metres Converter](https://valtrinity.com/tools/square-feet-to-square-metres/): Convert square feet to square metres (ft² to m²) with the formula and a quick table.
- [Hectares to Acres Converter](https://valtrinity.com/tools/hectares-to-acres/): Convert hectares to acres (ha to ac) with the formula and a quick table.
- [Acres to Hectares Converter](https://valtrinity.com/tools/acres-to-hectares/): Convert acres to hectares (ac to ha) with the formula and a quick table.
- [Acres to Square Feet Converter](https://valtrinity.com/tools/acres-to-square-feet/): Convert acres to square feet (ac to ft²) with the formula and a quick table.
- [Square Feet to Acres Converter](https://valtrinity.com/tools/square-feet-to-acres/): Convert square feet to acres (ft² to ac) with the formula and a quick table.
- [Square Kilometres to Square Miles Converter](https://valtrinity.com/tools/square-km-to-square-miles/): Convert square kilometres to square miles (km² to mi²) with the formula and a quick table.
- [Square Miles to Square Kilometres Converter](https://valtrinity.com/tools/square-miles-to-square-km/): Convert square miles to square kilometres (mi² to km²) with the formula and a quick table.
- [Degrees Celsius to Degrees Fahrenheit](https://valtrinity.com/tools/celsius-to-fahrenheit/): Convert degrees Celsius to degrees Fahrenheit (°C to °F) with the formula and a quick table.
- [Degrees Fahrenheit to Degrees Celsius](https://valtrinity.com/tools/fahrenheit-to-celsius/): Convert degrees Fahrenheit to degrees Celsius (°F to °C) with the formula and a quick table.
- [Degrees Celsius to Kelvins Converter](https://valtrinity.com/tools/celsius-to-kelvin/): Convert degrees Celsius to kelvins (°C to K) with the formula and a quick table.
- [Kelvins to Degrees Celsius Converter](https://valtrinity.com/tools/kelvin-to-celsius/): Convert kelvins to degrees Celsius (K to °C) with the formula and a quick table.
- [Degrees Fahrenheit to Kelvins Converter](https://valtrinity.com/tools/fahrenheit-to-kelvin/): Convert degrees Fahrenheit to kelvins (°F to K) with the formula and a quick table.
- [Kelvins to Degrees Fahrenheit Converter](https://valtrinity.com/tools/kelvin-to-fahrenheit/): Convert kelvins to degrees Fahrenheit (K to °F) with the formula and a quick table.
- [Miles per Hour to Kilometres per Hour](https://valtrinity.com/tools/mph-to-kmh/): Convert miles per hour to kilometres per hour (mph to km/h) with the formula and a quick table.
- [Kilometres per Hour to Miles per Hour](https://valtrinity.com/tools/kmh-to-mph/): Convert kilometres per hour to miles per hour (km/h to mph) with the formula and a quick table.
- [Knots to Miles per Hour Converter](https://valtrinity.com/tools/knots-to-mph/): Convert knots to miles per hour (kn to mph) with the formula and a quick table.
- [Miles per Hour to Knots Converter](https://valtrinity.com/tools/mph-to-knots/): Convert miles per hour to knots (mph to kn) with the formula and a quick table.
- [Metres per Second to Kilometres per Hour](https://valtrinity.com/tools/metres-per-second-to-kmh/): Convert metres per second to kilometres per hour (m/s to km/h) with the formula and a quick table.
- [Kilometres per Hour to Metres per Second](https://valtrinity.com/tools/kmh-to-metres-per-second/): Convert kilometres per hour to metres per second (km/h to m/s) with the formula and a quick table.
- [Speed Converter](https://valtrinity.com/tools/speed-converter/): Convert mph, km/h, metres per second, knots and Mach, with a handy speed table.
- [Bar to Pounds per Square Inch Converter](https://valtrinity.com/tools/bar-to-psi/): Convert bar to pounds per square inch (bar to psi) with the formula and a quick table.
- [Pounds per Square Inch to Bar Converter](https://valtrinity.com/tools/psi-to-bar/): Convert pounds per square inch to bar (psi to bar) with the formula and a quick table.
- [Kilopascals to Pounds per Square Inch](https://valtrinity.com/tools/kpa-to-psi/): Convert kilopascals to pounds per square inch (kPa to psi) with the formula and a quick table.
- [Pounds per Square Inch to Kilopascals](https://valtrinity.com/tools/psi-to-kpa/): Convert pounds per square inch to kilopascals (psi to kPa) with the formula and a quick table.
- [Millimetres of Mercury to Kilopascals](https://valtrinity.com/tools/mmhg-to-kpa/): Convert millimetres of mercury to kilopascals (mmHg to kPa) with the formula and a quick table.
- [Kilopascals to Millimetres of Mercury](https://valtrinity.com/tools/kpa-to-mmhg/): Convert kilopascals to millimetres of mercury (kPa to mmHg) with the formula and a quick table.
- [Inches of Mercury to Hectopascals Converter](https://valtrinity.com/tools/inhg-to-hpa/): Convert inches of mercury to hectopascals (inHg to hPa) with the formula and a quick table.
- [Hectopascals to Inches of Mercury Converter](https://valtrinity.com/tools/hpa-to-inhg/): Convert hectopascals to inches of mercury (hPa to inHg) with the formula and a quick table.
- [Pressure Converter](https://valtrinity.com/tools/pressure-converter/): Convert pascals, bar, psi, atmospheres, mmHg and inHg in one go.
- [Kilojoules to Kilocalories Converter](https://valtrinity.com/tools/kj-to-kcal/): Convert kilojoules to kilocalories (kJ to kcal) with the formula and a quick table.
- [Kilocalories to Kilojoules Converter](https://valtrinity.com/tools/kcal-to-kj/): Convert kilocalories to kilojoules (kcal to kJ) with the formula and a quick table.
- [Kilowatt Hours to British Thermal Units](https://valtrinity.com/tools/kwh-to-btu/): Convert kilowatt hours to British thermal units (kWh to BTU) with the formula and a quick table.
- [British Thermal Units to Kilowatt Hours](https://valtrinity.com/tools/btu-to-kwh/): Convert British thermal units to kilowatt hours (BTU to kWh) with the formula and a quick table.
- [Kilowatt Hours to Therms Converter](https://valtrinity.com/tools/kwh-to-therms/): Convert kilowatt hours to therms (kWh to thm) with the formula and a quick table.
- [Therms to Kilowatt Hours Converter](https://valtrinity.com/tools/therms-to-kwh/): Convert therms to kilowatt hours (thm to kWh) with the formula and a quick table.
- [Kilowatts to Horsepower Converter](https://valtrinity.com/tools/kw-to-horsepower/): Convert kilowatts to horsepower (kW to hp) with the formula and a quick table.
- [Horsepower to Kilowatts Converter](https://valtrinity.com/tools/horsepower-to-kw/): Convert horsepower to kilowatts (hp to kW) with the formula and a quick table.
- [Megabytes to Gigabytes Converter](https://valtrinity.com/tools/mb-to-gb/): Convert megabytes to gigabytes (MB to GB) with the formula and a quick table.
- [Gigabytes to Megabytes Converter](https://valtrinity.com/tools/gb-to-mb/): Convert gigabytes to megabytes (GB to MB) with the formula and a quick table.
- [Gigabytes to Terabytes Converter](https://valtrinity.com/tools/gb-to-tb/): Convert gigabytes to terabytes (GB to TB) with the formula and a quick table.
- [Terabytes to Gigabytes Converter](https://valtrinity.com/tools/tb-to-gb/): Convert terabytes to gigabytes (TB to GB) with the formula and a quick table.
- [Gigabytes to Gibibytes Converter](https://valtrinity.com/tools/gb-to-gib/): Convert gigabytes to gibibytes (GB to GiB) with the formula and a quick table.
- [Gibibytes to Gigabytes Converter](https://valtrinity.com/tools/gib-to-gb/): Convert gibibytes to gigabytes (GiB to GB) with the formula and a quick table.
- [Megabits per Second to Megabytes per Second](https://valtrinity.com/tools/mbps-to-megabytes-per-second/): Convert megabits per second to megabytes per second (Mbps to MB/s) with the formula and a quick table.
- [Megabytes per Second to Megabits per Second](https://valtrinity.com/tools/megabytes-per-second-to-mbps/): Convert megabytes per second to megabits per second (MB/s to Mbps) with the formula and a quick table.
- [Time Duration Converter](https://valtrinity.com/tools/time-duration-converter/): Convert seconds, minutes, hours, days and weeks, and clock times such as 01:30:00.
- [Degrees to Radians Converter](https://valtrinity.com/tools/degrees-to-radians/): Convert degrees to radians (° to rad) with the formula and a quick table.
- [Radians to Degrees Converter](https://valtrinity.com/tools/radians-to-degrees/): Convert radians to degrees (rad to °) with the formula and a quick table.
- [Angle Converter](https://valtrinity.com/tools/angle-converter/): Convert degrees, radians, gradians and turns, and degrees, minutes and seconds.
- [MPG Converter](https://valtrinity.com/tools/mpg-converter/): Convert fuel economy between UK mpg, US mpg, litres per 100 km and kilometres per litre.
- [US Cups to Millilitres Converter](https://valtrinity.com/tools/cups-to-ml/): Convert US cups to millilitres (cup to ml) with the formula and a quick table.
- [Millilitres to US Cups Converter](https://valtrinity.com/tools/ml-to-cups/): Convert millilitres to US cups (ml to cup) with the formula and a quick table.
- [Tablespoons to Millilitres Converter](https://valtrinity.com/tools/tablespoons-to-ml/): Convert tablespoons to millilitres (tbsp to ml) with the formula and a quick table.
- [Millilitres to Tablespoons Converter](https://valtrinity.com/tools/ml-to-tablespoons/): Convert millilitres to tablespoons (ml to tbsp) with the formula and a quick table.
- [Teaspoons to Millilitres Converter](https://valtrinity.com/tools/teaspoons-to-ml/): Convert teaspoons to millilitres (tsp to ml) with the formula and a quick table.
- [Millilitres to Teaspoons Converter](https://valtrinity.com/tools/ml-to-teaspoons/): Convert millilitres to teaspoons (ml to tsp) with the formula and a quick table.
- [Cooking Measurement Converter](https://valtrinity.com/tools/cooking-measurement-converter/): Convert cups, spoons and millilitres, and common ingredients between cups and grams.
- [Oven Temperature Converter](https://valtrinity.com/tools/oven-temperature-converter/): Convert oven temperatures between Celsius, Fahrenheit and gas mark, with a fan oven setting.
- [Binary to Decimal Converter](https://valtrinity.com/tools/binary-to-decimal/): Convert binary numbers to decimal, with the working shown step by step.
- [Decimal to Binary Converter](https://valtrinity.com/tools/decimal-to-binary/): Convert decimal numbers to binary, with the working shown step by step.
- [Hexadecimal to Decimal Converter](https://valtrinity.com/tools/hex-to-decimal/): Convert hexadecimal numbers to decimal, with the working shown step by step.
- [Decimal to Hexadecimal Converter](https://valtrinity.com/tools/decimal-to-hex/): Convert decimal numbers to hexadecimal, with the working shown step by step.
- [Binary to Hexadecimal Converter](https://valtrinity.com/tools/binary-to-hex/): Convert binary numbers to hexadecimal, with the working shown step by step.
- [Hexadecimal to Binary Converter](https://valtrinity.com/tools/hex-to-binary/): Convert hexadecimal numbers to binary, with the working shown step by step.
- [Octal to Decimal Converter](https://valtrinity.com/tools/octal-to-decimal/): Convert octal numbers to decimal, with the working shown step by step.
- [Decimal to Octal Converter](https://valtrinity.com/tools/decimal-to-octal/): Convert decimal numbers to octal, with the working shown step by step.
- [Decimal to Ternary Converter](https://valtrinity.com/tools/decimal-to-ternary/): Convert decimal numbers to ternary, with the working shown step by step.
- [Ternary to Decimal Converter](https://valtrinity.com/tools/ternary-to-decimal/): Convert ternary numbers to decimal, with the working shown step by step.
- [Binary to Octal Converter](https://valtrinity.com/tools/binary-to-octal/): Convert binary numbers to octal, with the working shown step by step.
- [Octal to Binary Converter](https://valtrinity.com/tools/octal-to-binary/): Convert octal numbers to binary, with the working shown step by step.
- [Roman Numeral Converter](https://valtrinity.com/tools/roman-numeral-converter/): Convert numbers from 1 to 3999 into Roman numerals, and Roman numerals back into numbers.
- [Number Base Converter](https://valtrinity.com/tools/number-base-converter/): Convert whole numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36.
- [Colour Converter](https://valtrinity.com/tools/colour-converter/): Convert HEX, RGB and HSL colours and check text contrast.
- [Shoe Size Converter](https://valtrinity.com/tools/shoe-size-converter/): Compare UK, US, EU and centimetre shoe sizes for men, women and children.
- [Unit Converter](https://valtrinity.com/tools/unit-converter/): Convert length, mass, volume, speed, data size and temperature.
- [Newton Metres to Pound-feet Converter](https://valtrinity.com/tools/newton-metres-to-pound-feet/): Convert newton metres to pound-feet (N·m to lb·ft) with the formula and a quick table.
- [Pound-feet to Newton Metres Converter](https://valtrinity.com/tools/pound-feet-to-newton-metres/): Convert pound-feet to newton metres (lb·ft to N·m) with the formula and a quick table.

## Maths Calculators

- [Maths Calculators](https://valtrinity.com/maths-calculators/): Solve equations, work with fractions and percentages, find areas and angles, and calculate averages, standard deviation and probability.
- [Decimal to Fraction Calculator](https://valtrinity.com/tools/decimal-to-fraction-calculator/): Turn a decimal into a fraction in lowest terms, including repeating decimals such as 0.333.
- [Scientific Calculator](https://valtrinity.com/tools/scientific-calculator/): Type a whole calculation with brackets, powers, roots, logs and trigonometry, and see the answer as you type.
- [Long Division Calculator](https://valtrinity.com/tools/long-division-calculator/): Divide any two numbers and see the quotient, the remainder, the decimal answer and every step of the working.
- [Exponent Calculator](https://valtrinity.com/tools/exponent-calculator/): Raise any number to a power, including negative, decimal and fraction exponents, with exact answers for whole numbers.
- [Logarithm Calculator](https://valtrinity.com/tools/logarithm-calculator/): Work out a logarithm to any base, find the natural log, the log to base 10 and base 2, or reverse it to find an antilog.
- [Scientific Notation Calculator](https://valtrinity.com/tools/scientific-notation-calculator/): Convert a number to scientific notation (standard form), engineering notation and E notation, or turn it back into a plain number.
- [Factorial Calculator](https://valtrinity.com/tools/factorial-calculator/): Work out n factorial exactly, even for large numbers, with the digit count, trailing zeros and the double factorial.
- [Square Root and Nth Root Calculator](https://valtrinity.com/tools/square-root-calculator/): Find the square root, cube root or any other root of a number, in simplest radical form, with a check for perfect powers.
- [Rounding and Significant Figures Calculator](https://valtrinity.com/tools/rounding-calculator/): Round a number to decimal places, tens and hundreds, or significant figures, using the rule you choose, and count the significant figures in it.
- [Fraction Calculator](https://valtrinity.com/tools/fraction-calculator/): Add, subtract, multiply and divide fractions, simplify them and convert to decimals, with steps.
- [Ratio Calculator](https://valtrinity.com/tools/ratio-calculator/): Simplify ratios, scale them up or down, solve a proportion and share a total in a ratio.
- [Percentage Calculator](https://valtrinity.com/tools/percentage-calculator/): Work out percentages, percentage change and increases or decreases.
- [Reverse Percentage Calculator](https://valtrinity.com/tools/reverse-percentage-calculator/): Find the original price or amount before a percentage increase or decrease was applied.
- [Percentage Point Calculator](https://valtrinity.com/tools/percentage-point-calculator/): Find the difference between two percentages in percentage points, and compare it with the percentage change.
- [Percentage Difference and Percent Error Calculator](https://valtrinity.com/tools/percentage-difference-calculator/): Find the percentage difference between two values, or the percent error of a measurement against the true value.
- [Quadratic Equation Solver](https://valtrinity.com/tools/quadratic-equation-solver/): Solve ax² + bx + c = 0 with the quadratic formula, with the discriminant, exact roots, the vertex and the working.
- [Linear Equation Solver](https://valtrinity.com/tools/linear-equation-solver/): Solve a linear equation such as 3x + 4 = x + 10 for x, with every step and an exact fraction answer.
- [Simultaneous Equations Solver](https://valtrinity.com/tools/simultaneous-equations-solver/): Solve two equations with two unknowns, or three equations with three, with exact answers and a check for no solution.
- [Cubic Equation Solver](https://valtrinity.com/tools/cubic-equation-solver/): Solve ax³ + bx² + cx + d = 0 for all three roots, real and complex, with exact roots when they are rational.
- [Matrix Calculator](https://valtrinity.com/tools/matrix-calculator/): Add, subtract and multiply matrices up to 4 by 4, and find a determinant, inverse, transpose, trace, rank or power, with exact fractions.
- [Vector Calculator](https://valtrinity.com/tools/vector-calculator/): Add and subtract vectors, and find the dot product, cross product, magnitude, angle, unit vector and projection.
- [Arithmetic Sequence Calculator](https://valtrinity.com/tools/arithmetic-sequence-calculator/): Find any term and the sum of an arithmetic sequence, or work out the first term and common difference from two known terms.
- [Geometric Sequence Calculator](https://valtrinity.com/tools/geometric-sequence-calculator/): Find any term, the sum of the first n terms and the sum to infinity of a geometric sequence.
- [Complex Number Calculator](https://valtrinity.com/tools/complex-number-calculator/): Add, subtract, multiply and divide complex numbers, and find the modulus, argument, conjugate, square root and powers.
- [Equation of a Line and Slope Calculator](https://valtrinity.com/tools/line-equation-calculator/): Find the equation, slope, angle, percentage grade and intercepts of a straight line from two points, a point and a slope, or a general equation.
- [Distance and Midpoint Calculator](https://valtrinity.com/tools/distance-between-points-calculator/): Find the distance between two points and their midpoint in two or three dimensions, or find the other end of a line from one end and the midpoint.
- [Pythagorean Theorem Calculator](https://valtrinity.com/tools/pythagoras-calculator/): Find the missing side of a right-angled triangle, with area, perimeter and angles.
- [Triangle Calculator](https://valtrinity.com/tools/triangle-calculator/): Enter any three known values of a triangle, sides and angles, and get the rest, with the area, perimeter and the sine and cosine rule working.
- [Arc Length Calculator](https://valtrinity.com/tools/arc-length-calculator/): Find the length of an arc, the area of a sector, the chord and the segment from the radius and an angle.
- [Regular Polygon Calculator](https://valtrinity.com/tools/regular-polygon-calculator/): Find the area, perimeter, angles, apothem and diagonals of a regular polygon from its number of sides and one measurement.
- [Trigonometry Calculator](https://valtrinity.com/tools/trigonometry-calculator/): Find the sine, cosine, tangent and their reciprocals of any angle with exact values, or find the angle from a sine, cosine, tangent or two sides.
- [Area and Volume Calculator](https://valtrinity.com/tools/area-volume-calculator/): Work out the area, perimeter, volume and surface area of common shapes in the units you choose.
- [Standard Deviation Calculator](https://valtrinity.com/tools/standard-deviation-calculator/): Find the standard deviation and variance of a list of numbers, for a sample or a whole population, with the working.
- [Quartile Calculator](https://valtrinity.com/tools/quartile-calculator/): Find the quartiles, median, interquartile range and outliers of a list of numbers, using the method your course or spreadsheet uses.
- [Permutation and Combination Calculator](https://valtrinity.com/tools/permutation-combination-calculator/): Work out nPr and nCr exactly, with and without repeats, for choosing r items from n.
- [Binomial Probability Calculator](https://valtrinity.com/tools/binomial-probability-calculator/): Find the chance of exactly, at most or at least k successes in n trials, with the mean and standard deviation.
- [Confidence Interval Calculator](https://valtrinity.com/tools/confidence-interval-calculator/): Find the confidence interval for a mean from a sample, or for a proportion, with the margin of error.
- [Sample Size Calculator](https://valtrinity.com/tools/sample-size-calculator/): Work out how many people to survey for a proportion, or how many measurements for a mean, for the margin of error you want.
- [Weighted Average Calculator](https://valtrinity.com/tools/weighted-average-calculator/): Find the weighted average of values that count for different amounts, such as grades with different weightings.
- [Probability Calculator](https://valtrinity.com/tools/probability-calculator/): Work out the chance of two events happening together or either happening, for independent, exclusive and dependent events, and repeated trials.
- [Normal Distribution and Z-Score Calculator](https://valtrinity.com/tools/normal-distribution-calculator/): Find z-scores, the probability of a value being below, above or between limits in a normal distribution, or the value for a given probability.
- [Linear Regression and Correlation Calculator](https://valtrinity.com/tools/linear-regression-calculator/): Fit a straight line to pairs of values and get the slope, intercept, correlation coefficient, r squared and a prediction.
- [Average Calculator](https://valtrinity.com/tools/average-calculator/): Find the mean, median, mode, range, sum, count and standard deviation of a list of numbers.
- [GCD and LCM Calculator](https://valtrinity.com/tools/gcd-lcm-calculator/): Find the highest common factor and lowest common multiple of two or more numbers.
- [Prime Number Checker](https://valtrinity.com/tools/prime-number-checker/): Check whether numbers are prime, see their prime factors and find the next prime.
- [Modulo Calculator](https://valtrinity.com/tools/modulo-calculator/): Find the remainder of a division, a power modulo a number, or the modular inverse, with correct handling of negative numbers.
- [Fibonacci Calculator](https://valtrinity.com/tools/fibonacci-calculator/): Find any Fibonacci number exactly, list the first terms, or check whether a number is in the sequence.
- [Factors and Prime Factorisation Calculator](https://valtrinity.com/tools/factors-calculator/): List every factor of a number, see its prime factorisation with the division steps, and learn whether it is prime, square or perfect.

## Money and Tax Calculators

- [Money and Tax Calculators](https://valtrinity.com/money-and-tax-calculators/): Work out take-home pay, stamp duty, VAT, compound interest, savings goals and more for the UK.
- [Capital Gains Tax Calculator](https://valtrinity.com/tools/capital-gains-tax-calculator/): Estimate capital gains tax on selling shares or property for 2026/27, with the 18% and 24% rates.
- [Dividend Tax Calculator](https://valtrinity.com/tools/dividend-tax-calculator/): Estimate dividend tax on top of your salary for 2026/27, with the dividend allowance and each band.
- [UK Inheritance Tax Calculator](https://valtrinity.com/tools/inheritance-tax-calculator/): Estimate inheritance tax on an estate for 2026/27, with the residence nil rate band, spouse and charity exemptions.
- [UK Income Tax Calculator](https://valtrinity.com/tools/uk-income-tax-calculator/): Work out your income tax for 2026/27 and see the tax bands and rates for England, Wales, Northern Ireland and Scotland.
- [National Insurance Calculator](https://valtrinity.com/tools/national-insurance-calculator/): Work out employee Class 1 National Insurance for 2026/27, and the employer's share, from your pay.
- [Bonus Tax Calculator](https://valtrinity.com/tools/bonus-tax-calculator/): See how much of a bonus you keep after income tax and National Insurance in 2026/27.
- [Pension Tax Relief Calculator](https://valtrinity.com/tools/pension-tax-relief-calculator/): See how much tax relief you get on pension contributions in 2026/27 and what they really cost you.
- [Salary Sacrifice Calculator](https://valtrinity.com/tools/salary-sacrifice-calculator/): Find the tax and National Insurance you save by giving up salary for pension in 2026/27.
- [Savings Interest Tax Calculator](https://valtrinity.com/tools/savings-interest-tax-calculator/): Check if you owe tax on savings interest in 2026/27, using the Personal Savings Allowance and the starting rate.
- [VAT Calculator](https://valtrinity.com/tools/vat-calculator/): Add VAT to a price or take it out again at 20%, 5%, 0% or any rate you choose.
- [US Income Tax Calculator](https://valtrinity.com/tools/us-income-tax-calculator/): Estimate US federal income tax for 2026 by filing status, with the standard deduction and each bracket.
- [US Paycheck Calculator](https://valtrinity.com/tools/us-paycheck-calculator/): Estimate US take-home pay after federal tax, Social Security, Medicare and state income tax for 2026.
- [US Sales Tax Calculator](https://valtrinity.com/tools/us-sales-tax-calculator/): Add sales tax to a price or take it out again, using the state rate and an editable local rate.
- [401(k) Calculator](https://valtrinity.com/tools/401k-calculator/): Project your 401(k) balance with your contributions, employer match, pay rises and 2026 limits.
- [Roth IRA Calculator](https://valtrinity.com/tools/roth-ira-calculator/): Find your 2026 Roth IRA contribution limit after the income phase-out, and see how it could grow.
- [US Capital Gains Tax Calculator](https://valtrinity.com/tools/us-capital-gains-tax-calculator/): Estimate US federal tax on short and long term gains for 2026, with the 0%, 15% and 20% rates and NIIT.
- [Self-Employment Tax Calculator](https://valtrinity.com/tools/self-employment-tax-calculator/): Estimate US self-employment tax for 2026 with the 92.35% factor and the Social Security wage base.
- [Loan & Mortgage Calculator](https://valtrinity.com/tools/loan-calculator/): Estimate monthly repayments, total interest and the effect of overpaying.
- [UK Mortgage Calculator](https://valtrinity.com/tools/mortgage-calculator/): Work out the monthly payment, total interest and a year by year balance for a repayment or interest only mortgage.
- [US Mortgage Calculator](https://valtrinity.com/tools/us-mortgage-calculator/): Work out a monthly mortgage payment with property tax, homeowners insurance, PMI and HOA dues.
- [Commercial Stamp Duty Calculator](https://valtrinity.com/tools/commercial-stamp-duty-calculator/): Work out stamp duty (SDLT) on a freehold commercial or mixed use property in England and Northern Ireland.
- [Stamp Duty Calculator by Date](https://valtrinity.com/tools/historic-stamp-duty-calculator/): See the stamp duty on a home in England or Northern Ireland at any date since December 2014.
- [Net Initial Yield Calculator](https://valtrinity.com/tools/net-initial-yield-calculator/): Work out the net initial yield on a commercial property after costs, with stamp duty and fees included.
- [Mortgage Affordability Calculator](https://valtrinity.com/tools/mortgage-affordability-calculator/): Estimate how much you could borrow from your income, and the monthly payment at several income multiples.
- [Remortgage Calculator](https://valtrinity.com/tools/remortgage-calculator/): Compare your current mortgage with a new deal, including fees and exit charges, and see when switching pays off.
- [Buy to Let Mortgage Calculator](https://valtrinity.com/tools/buy-to-let-mortgage-calculator/): Check the rental cover a buy to let lender will want, the most you could borrow and the yearly profit.
- [Interest Only vs Repayment Mortgage Calculator](https://valtrinity.com/tools/interest-only-vs-repayment-mortgage-calculator/): Compare interest only and repayment mortgages on monthly payment, total cost and the debt left at the end.
- [Stamp Duty Calculator](https://valtrinity.com/tools/stamp-duty-calculator/): Estimate stamp duty (SDLT), LBTT in Scotland or LTT in Wales on a home purchase.
- [Mortgage Overpayment Calculator](https://valtrinity.com/tools/mortgage-overpayment-calculator/): See the interest and time you save by overpaying a mortgage each month or in one lump sum.
- [Rental Yield Calculator](https://valtrinity.com/tools/rental-yield-calculator/): Work out gross and net rental yield, running costs and cash flow with an interest-only mortgage.
- [UK Pension Calculator](https://valtrinity.com/tools/pension-calculator/): Project a pension pot with your contributions, tax relief at source or net pay, employer money and growth.
- [UK Retirement Calculator](https://valtrinity.com/tools/retirement-calculator/): Compare the savings you need for the income you want with your projected pot, including the State Pension.
- [ISA Allowance Tracker](https://valtrinity.com/tools/isa-allowance-tracker/): Track how much of your £20,000 ISA allowance for 2026/27 you have used and what is left.
- [Emergency Fund Calculator](https://valtrinity.com/tools/emergency-fund-calculator/): Find the size of emergency fund you need from your essential costs, and how long it takes to build.
- [Budget Planner](https://valtrinity.com/tools/budget-planner/): Split your take-home pay into needs, wants and savings with the 50/30/20 rule, or your own shares.
- [Net Worth Calculator](https://valtrinity.com/tools/net-worth-calculator/): Add up what you own and what you owe to find your net worth.
- [Cost Per Wear Calculator](https://valtrinity.com/tools/cost-per-wear-calculator/): Find what an item of clothing really costs each time you wear it, and how many wears justify the price.
- [Compound Interest Calculator](https://valtrinity.com/tools/compound-interest-calculator/): See how savings grow with regular deposits, a chosen interest rate and compounding.
- [Savings Goal Calculator](https://valtrinity.com/tools/savings-goal-calculator/): Find out how long it takes to reach a savings goal, or how much to save each month.
- [Overtime Pay Calculator](https://valtrinity.com/tools/overtime-pay-calculator/): Estimate overtime pay for a week, day by day.
- [Student Loan Repayment Calculator](https://valtrinity.com/tools/student-loan-repayment-calculator/): Work out your monthly and yearly student loan repayment for Plans 1, 2, 4 and 5, or a postgraduate loan.
- [Redundancy Pay Calculator](https://valtrinity.com/tools/redundancy-pay-calculator/): Estimate statutory redundancy pay from your age, years of service and weekly pay for 2026/27.
- [Holiday Entitlement and Pay Calculator](https://valtrinity.com/tools/holiday-pay-calculator/): Work out annual leave and holiday pay for a fixed week, part year or irregular hours in 2026/27.
- [Pay Rise Calculator](https://valtrinity.com/tools/pay-rise-calculator/): Work out a pay rise as a percentage or an amount, with the extra take-home pay and the effect of inflation.
- [Part-Time Salary Calculator](https://valtrinity.com/tools/part-time-salary-calculator/): Convert a full-time salary into the pay for part-time hours, with monthly, weekly and hourly figures.
- [Freelance Day Rate Calculator](https://valtrinity.com/tools/freelance-day-rate-calculator/): Work out the day rate you need to charge to reach your target income after costs, holidays and time you cannot bill.
- [Statutory Sick Pay Calculator](https://valtrinity.com/tools/statutory-sick-pay-calculator/): Estimate Statutory Sick Pay for 2026/27 from your average weekly earnings and the days you are off.
- [Statutory Maternity Pay Calculator](https://valtrinity.com/tools/statutory-maternity-pay-calculator/): Estimate Statutory Maternity Pay for 2026/27, week by week, from your average weekly earnings.
- [Minimum Wage Checker](https://valtrinity.com/tools/minimum-wage-checker/): Check whether your pay meets the UK National Minimum Wage or National Living Wage rates from April 2026.
- [Commission Calculator](https://valtrinity.com/tools/commission-calculator/): Work out commission on sales at a flat rate or in bands, with or without a base salary.
- [UK Take-Home Pay Calculator](https://valtrinity.com/tools/uk-take-home-pay-calculator/): Work out pay after income tax, National Insurance, student loan and pension for 2026/27.
- [Hourly to Salary Calculator](https://valtrinity.com/tools/hourly-to-salary-calculator/): Convert pay between hourly, daily, weekly, monthly and annual amounts.
- [Profit Margin Calculator](https://valtrinity.com/tools/profit-margin-calculator/): Work out profit, margin and markup from cost and price, or find the price for a target margin.
- [EU VAT Calculator](https://valtrinity.com/tools/eu-vat-calculator/): Add or remove VAT at the standard or reduced rate of any EU country, with a dated table of rates.
- [Etsy Fee Calculator (UK)](https://valtrinity.com/tools/etsy-fee-calculator/): Estimate Etsy fees on a UK sale and the profit left, with editable rates.
- [Amazon Seller Fee Calculator (UK)](https://valtrinity.com/tools/amazon-seller-fee-calculator/): Estimate Amazon UK referral fees, plan fees and profit on a sale, with VAT taken out.
- [YouTube Earnings Estimator](https://valtrinity.com/tools/youtube-earnings-estimator/): Estimate a monthly and yearly income range from views and an editable RPM for long videos and Shorts.
- [Twitch Earnings Estimator](https://valtrinity.com/tools/twitch-earnings-estimator/): Estimate monthly income from subscribers, Bits and ads with editable prices and revenue share.
- [NPV and IRR Calculator](https://valtrinity.com/tools/npv-calculator/): Work out the net present value, internal rate of return and payback time of a series of yearly cash flows.
- [ROI Calculator](https://valtrinity.com/tools/roi-calculator/): Calculate return on investment as a percentage, with the gain in pounds and the return per year.
- [Depreciation Calculator](https://valtrinity.com/tools/depreciation-calculator/): Spread the cost of an asset over its life with straight line or reducing balance depreciation, year by year.
- [Break Even Calculator](https://valtrinity.com/tools/break-even-calculator/): Find how many units you must sell to cover your costs, and how many to reach a target profit.
- [Employee Cost Calculator](https://valtrinity.com/tools/employee-cost-calculator/): Work out what an employee really costs you in a year, with employer National Insurance and pension for 2026/27.
- [Late Payment Interest Calculator](https://valtrinity.com/tools/late-payment-interest-calculator/): Work out the statutory interest and fixed compensation you can claim when another business pays an invoice late.
- [Business Mileage Allowance Calculator](https://valtrinity.com/tools/mileage-allowance-calculator/): Work out HMRC approved mileage payments, or the flat rate you can claim as self-employed, for the 2026/27 tax year.
- [Working From Home Expenses Calculator](https://valtrinity.com/tools/working-from-home-expenses-calculator/): Add up the simplified expenses flat rate for working from home as self-employed, month by month, and compare it with your actual costs.
- [Unit Economics Calculator](https://valtrinity.com/tools/unit-economics-calculator/): See what each sale really earns after product cost, fees, shipping and refunds, and the price needed for the margin you want.
- [MRR and ARR Calculator](https://valtrinity.com/tools/subscription-mrr-arr-calculator/): Turn your plans into monthly and annual recurring revenue, and track how the month moved with expansion and churn.
- [Churn and Retention Calculator](https://valtrinity.com/tools/churn-and-retention-calculator/): Find your customer churn and retention rate, how long a customer stays, their lifetime value and where your customer count is heading.
- [Net Promoter Score Calculator](https://valtrinity.com/tools/net-promoter-score-calculator/): Turn survey scores from 0 to 10 into your Net Promoter Score, with the split of promoters, passives and detractors and a margin of error.
- [Payment Terms Due Date Calculator](https://valtrinity.com/tools/payment-terms-due-date-calculator/): Find the due date for net 30, 30 days from month end, end of next month and other payment terms, with early payment discount dates.
- [12 Month Cash Flow Forecast](https://valtrinity.com/tools/cash-flow-forecast/): Build a 12 month cash flow forecast with money in and out, growth, one-off and quarterly payments, and see when the balance dips.
- [Meeting Cost Calculator](https://valtrinity.com/tools/meeting-cost-calculator/): See what a meeting costs as it happens, from the salaries of everyone in the room, with a running total you can start and stop.
- [Reorder Point and Safety Stock Calculator](https://valtrinity.com/tools/reorder-point-calculator/): Work out when to reorder stock, how much safety stock covers the risk of running out, and the order size that keeps costs lowest.
- [IBAN Validator](https://valtrinity.com/tools/iban-validator/): Check an IBAN for the right length and valid check digits, and see the country.
- [VAT Number Format Checker](https://valtrinity.com/tools/vat-number-validator/): Check that a UK or EU VAT number is written in the right format. Format check only.
- [National Insurance Number Checker](https://valtrinity.com/tools/ni-number-validator/): Check that a National Insurance number is in the right format. Format check only.
- [Card Number Validator](https://valtrinity.com/tools/card-number-validator/): Check card numbers with the Luhn check digit test and see the likely card network.
- [APR Calculator](https://valtrinity.com/tools/apr-calculator/): Find the APR of a loan or credit offer, including fees, from the amount, the term and the rate or the monthly payment.
- [Credit Card Repayment Calculator](https://valtrinity.com/tools/credit-card-repayment-calculator/): See how long a credit card balance takes to clear and the interest it costs, or the payment needed for a set time.
- [Debt Payoff Calculator](https://valtrinity.com/tools/debt-payoff-calculator/): Compare the snowball and avalanche methods for clearing several debts, with time and interest for each.
- [Loan Comparison Calculator](https://valtrinity.com/tools/loan-comparison-calculator/): Compare up to three loans side by side on monthly payment, interest, fees and total cost.
- [Car Finance Calculator](https://valtrinity.com/tools/car-finance-calculator/): Work out the monthly payment on hire purchase or a personal contract plan with a final payment.
- [Lease vs Buy Car Calculator](https://valtrinity.com/tools/lease-vs-buy-car-calculator/): Compare the real cost of leasing a car with buying it on finance and selling it at the end.
- [Currency Converter](https://valtrinity.com/tools/currency-converter/): Convert between currencies using the latest European Central Bank reference rates, with a swap button.
- [Inflation Adjusted Value Calculator](https://valtrinity.com/tools/inflation-adjusted-value-calculator/): See what an amount will cost or be worth in future money using a yearly inflation rate you choose, or find the rate between two prices.

## Health and Fitness Calculators

- [Health and Fitness Calculators](https://valtrinity.com/health-calculators/): Check your BMI, daily calories, body fat, heart rate zones and running pace, and plan a pregnancy timeline or a better night's sleep.
- [BMI Calculator](https://valtrinity.com/tools/bmi-calculator/): Work out body mass index in metric or stones and pounds.
- [Ideal Weight Calculator](https://valtrinity.com/tools/ideal-weight-calculator/): Compare four published ideal weight formulas with the healthy BMI range for your height.
- [Body Fat Calculator](https://valtrinity.com/tools/body-fat-calculator/): Estimate your body fat percentage from a tape measure using the US Navy method.
- [Waist to Height and Hip Ratio Calculator](https://valtrinity.com/tools/waist-to-height-ratio-calculator/): Check whether your waist is under half your height, and add your hips for the waist to hip ratio.
- [Body Surface Area Calculator](https://valtrinity.com/tools/body-surface-area-calculator/): Work out body surface area in square metres with the Mosteller, Du Bois, Haycock and Gehan-George formulas.
- [Smoking Cost Calculator](https://valtrinity.com/tools/smoking-cost-calculator/): Add up what cigarettes cost you a day, a month and a year, and how that grows over time.
- [Macro Calculator](https://valtrinity.com/tools/macro-calculator/): Turn a daily calorie target into grams of carbohydrate, protein and fat.
- [Protein Intake Calculator](https://valtrinity.com/tools/protein-intake-calculator/): Find how many grams of protein suit your weight and goal, from general health to building muscle.
- [Water Intake Calculator](https://valtrinity.com/tools/water-intake-calculator/): See how much fluid adults need in a day, with extra for exercise, pregnancy and breastfeeding.
- [Calorie Deficit and Weight Loss Time Calculator](https://valtrinity.com/tools/calorie-deficit-calculator/): Find the daily calorie gap and calories to eat for a target date, or how long a chosen pace will take.
- [Alcohol Units Calculator](https://valtrinity.com/tools/alcohol-units-calculator/): Count UK alcohol units for any drink and see your week against the 14 unit guideline.
- [Caffeine Intake Calculator](https://valtrinity.com/tools/caffeine-intake-calculator/): Add up caffeine from coffee, tea, cola, energy drinks and chocolate and compare it with a daily limit.
- [Calorie Calculator](https://valtrinity.com/tools/calorie-calculator/): Estimate the calories your body uses at rest and the daily energy you need to keep your weight.
- [Pregnancy Due Date Calculator](https://valtrinity.com/tools/pregnancy-due-date-calculator/): Work out an estimated due date from the first day of your last period, using the NHS method.
- [Ovulation Calculator](https://valtrinity.com/tools/ovulation-calculator/): Estimate your likely ovulation date and fertile window from the first day of your last period.
- [Conception Date Calculator](https://valtrinity.com/tools/conception-date-calculator/): Work backwards from a due date or the first day of your last period to find when conception probably happened.
- [Pregnancy Weight Gain Calculator](https://valtrinity.com/tools/pregnancy-weight-gain-calculator/): See the Institute of Medicine weight gain range for your pre-pregnancy BMI, singleton or twins.
- [Heart Rate Zones and Max Heart Rate Calculator](https://valtrinity.com/tools/target-heart-rate-calculator/): Find your heart rate zones from age and resting pulse, with the Karvonen method.
- [VO2 Max Calculator](https://valtrinity.com/tools/vo2-max-calculator/): Estimate VO2 max from a 12-minute Cooper run or from your resting and maximum heart rate.
- [One Rep Max Calculator](https://valtrinity.com/tools/one-rep-max-calculator/): Estimate your one rep max from a set of reps with Epley, Brzycki and four other formulas.
- [Calories Burned Calculator](https://valtrinity.com/tools/calories-burned-calculator/): Estimate calories burned in over 70 activities, using MET values from the Compendium of Physical Activities.
- [Running Pace Calculator](https://valtrinity.com/tools/running-pace-calculator/): Work out pace, finish time or distance for a run, with splits and race times at your pace.
- [Race Time Predictor](https://valtrinity.com/tools/race-time-predictor/): Predict your 5K, 10K, half marathon and marathon times from a recent race using the Riegel formula.
- [Steps to Distance Calculator](https://valtrinity.com/tools/steps-to-distance-calculator/): Turn steps into kilometres and miles using your height or your own stride length, or work out steps for a distance.
- [Cycling Speed Calculator](https://valtrinity.com/tools/cycling-speed-calculator/): Find average speed from distance and time, or work out speed from gearing and cadence.
- [Swim Pace Calculator](https://valtrinity.com/tools/swim-pace-calculator/): Find your pace per 100 metres or yards, your finish time, and lap times for your pool.
- [Rowing Pace Calculator](https://valtrinity.com/tools/rowing-pace-calculator/): Convert rowing machine split per 500 metres, time, distance and watts.
- [Sleep Calculator](https://valtrinity.com/tools/sleep-calculator/): Find the times to go to bed or wake up so you finish a full 90 minute sleep cycle.
- [Sleep Debt Calculator](https://valtrinity.com/tools/sleep-debt-calculator/): Add up seven nights of sleep and see how many hours short or ahead you are of your target.

## Date and Time Calculators

- [Date and Time Calculators](https://valtrinity.com/date-and-time-calculators/): Count the days between dates, add or subtract time, find your exact age, check week numbers and convert between time zones.
- [Age Calculator](https://valtrinity.com/tools/age-calculator/): Find an exact age in years, months and days, and the next birthday.
- [Days Until Calculator](https://valtrinity.com/tools/days-until-calculator/): Count the days, weeks and months until any date.
- [Add Days to Date Calculator](https://valtrinity.com/tools/add-days-to-date-calculator/): Add or subtract days, weeks, months or years from a date.
- [Date Calculator](https://valtrinity.com/tools/date-calculator/): Add or subtract years, months, weeks and days from any date, with the month end rules shown.
- [Day of the Week Calculator](https://valtrinity.com/tools/day-of-week-calculator/): Find the day of the week for any date in the past or future, and see how that date falls in later years.
- [Birthday Calculator](https://valtrinity.com/tools/birthday-calculator/): See the day you were born, your next birthday and half birthday, how many days you have lived and the dates of your milestones.
- [Julian Date Converter](https://valtrinity.com/tools/julian-date-converter/): Convert a date and time to a Julian date, Julian day number, modified Julian date and day of year format, and back.
- [UK School Year Calculator](https://valtrinity.com/tools/uk-school-year-calculator/): Find a child's school year group in England from their date of birth, using the 1 September cut-off.
- [Weekday Counter](https://valtrinity.com/tools/weekday-counter/): Count how many Mondays, Tuesdays and every other weekday fall between two dates.
- [Date Format Converter](https://valtrinity.com/tools/date-format-converter/): Show a date in UK, US, international standard and written formats, and check whether a numeric date such as 03/04/2026 is ambiguous.
- [Date Difference Calculator](https://valtrinity.com/tools/date-difference-calculator/): Count the years, months and days between two dates, plus total days, weeks and working days.
- [Working Days Calculator](https://valtrinity.com/tools/working-days-calculator/): Add or subtract working days from a date, skipping weekends and England and Wales bank holidays.
- [Hours Calculator](https://valtrinity.com/tools/hours-calculator/): Work out hours worked for each day of the week and the total.
- [Time Card Calculator](https://valtrinity.com/tools/time-card-calculator/): Work out hours and weekly pay from clock in and clock out times.
- [Time Calculator](https://valtrinity.com/tools/time-calculator/): Add and subtract hours, minutes and seconds, and see the total as hh:mm:ss and in decimal hours.
- [Military Time Converter](https://valtrinity.com/tools/military-time-converter/): Convert 24 hour military time to 12 hour clock time and back, with the way it is said aloud.
- [Hours to Decimal Calculator](https://valtrinity.com/tools/hours-to-decimal-calculator/): Convert hours and minutes to decimal hours for timesheets and invoices, or decimal hours back to hours and minutes.
- [Sunrise and Sunset Calculator](https://valtrinity.com/tools/sunrise-sunset-calculator/): Work out sunrise, sunset, solar noon and day length for any place and date from its latitude and longitude.
- [Meeting Planner](https://valtrinity.com/tools/meeting-planner/): Find the hours when working days overlap across up to four time zones, with daylight saving taken into account.
- [Time Zone Converter](https://valtrinity.com/tools/time-zone-converter/): Convert a date and time from one city to up to four others, with UTC offsets and day changes.
- [Pomodoro Timer](https://valtrinity.com/tools/pomodoro-timer/): Work in focused sessions with short and long breaks in between.
- [Multiple Timers](https://valtrinity.com/tools/multiple-timers/): Run several named countdown timers at once, such as for cooking, with a sound when each one finishes.
- [Alarm Clock](https://valtrinity.com/tools/alarm-clock/): Set one or more alarms for a time of day, with a snooze button and a repeat each day. The page must stay open.
- [Countdown Timer and Stopwatch](https://valtrinity.com/tools/countdown-timer/): Count down to a date and time with a live display, or time something with a simple stopwatch.
- [Week Number Calculator](https://valtrinity.com/tools/week-number-calculator/): Find the week number for any date, or the dates of a given week.
- [Leap Year Checker](https://valtrinity.com/tools/leap-year-checker/): Check if a year is a leap year and see the next ones.
- [Zodiac Sign Finder](https://valtrinity.com/tools/zodiac-sign-finder/): Find your western star sign and Chinese zodiac animal.
- [Easter Date Calculator](https://valtrinity.com/tools/easter-date-calculator/): Find the date of Easter Sunday for any year from 1583, with Good Friday, Easter Monday and the other dates that follow it.
- [Moon Phase Calculator](https://valtrinity.com/tools/moon-phase-calculator/): See the phase of the moon on any date, how much is lit, its age, and the dates of the next new and full moons.
- [UK Bank Holidays](https://valtrinity.com/tools/uk-bank-holidays/): Bank holidays in England and Wales, Scotland and Northern Ireland for 2026 and 2027, from GOV.UK.
- [Printable Calendar Generator](https://valtrinity.com/tools/printable-calendar-generator/): Make a printable monthly or yearly calendar that starts on Monday or Sunday, with week numbers and UK bank holidays if you wish.
- [Chinese Zodiac Calculator](https://valtrinity.com/tools/chinese-zodiac-calculator/): Find your Chinese zodiac animal and element from your date of birth, using the real date of Chinese New Year.
- [Nth Weekday of the Month Calculator](https://valtrinity.com/tools/nth-weekday-calculator/): Find the first, second, third, fourth or last Monday (or any day) of a month, such as the last Friday in June.
- [When Do the Clocks Change?](https://valtrinity.com/tools/clocks-change-dates/): Dates and times of the clock changes in the UK, Europe, the US and Canada for any year, with the length of the changeover days.

## Everyday Calculators

- [Everyday Calculators](https://valtrinity.com/calculators/): Work out tips and split bills, plan DIY and garden jobs, compare prices, check fuel costs and calculate school grades.
- [Roof Pitch Calculator](https://valtrinity.com/tools/roof-pitch-calculator/): Find roof pitch angle, ratio and rafter length from the rise and run.
- [Decking Calculator](https://valtrinity.com/tools/decking-calculator/): Work out how many decking boards, joists and screws you need for a deck of any size.
- [Concrete Calculator](https://valtrinity.com/tools/concrete-calculator/): Work out the concrete for a slab, footing or round post holes, in cubic metres, tonnes and bags, with a DIY mix.
- [Paint Calculator](https://valtrinity.com/tools/paint-calculator/): Find out how many litres of paint a room needs, and which tin sizes to buy, allowing for doors, windows and coats.
- [Wallpaper Calculator](https://valtrinity.com/tools/wallpaper-calculator/): Count the rolls of wallpaper for a room from the wall height, roll size and pattern repeat.
- [Tile and Paving Calculator](https://valtrinity.com/tools/tile-calculator/): Count the tiles or paving slabs for a floor, wall or patio, with joints and waste, plus grout or sub-base.
- [Carpet Calculator](https://valtrinity.com/tools/carpet-calculator/): Work out how much carpet to order from a 3.66, 4 or 5 metre roll, which way to cut it, and the joins.
- [Brick and Block Calculator](https://valtrinity.com/tools/brick-calculator/): Count the bricks or blocks for a wall of any length and height, with openings, joints, waste and mortar.
- [Stair Calculator](https://valtrinity.com/tools/stair-calculator/): Plan a staircase: number of steps, height of each riser, going and pitch, checked against the England building rules for stairs in a home.
- [Fence Panel and Post Calculator](https://valtrinity.com/tools/fence-calculator/): Count the panels, posts and gravel boards for a fence run, allowing for gates and separate sections.
- [Square Metre Calculator for Rooms](https://valtrinity.com/tools/square-metre-calculator/): Add up the floor area of several rooms in square metres, square feet and square yards, and take off cut-outs.
- [Radiator Size Calculator (BTU)](https://valtrinity.com/tools/radiator-btu-calculator/): Estimate how much heat a room loses, and the radiator output in BTU and watts to heat it, from its walls, windows, floor and roof.
- [Electricity Cost Calculator](https://valtrinity.com/tools/electricity-cost-calculator/): Work out what appliances cost to run a day, month and year from their power in watts, the hours used and your price per kWh.
- [Split Bill Calculator](https://valtrinity.com/tools/split-bill-calculator/): Split a bill with a tip, by equal shares, uneven shares or what each person ordered, with rounding.
- [Unit Price Comparison Calculator](https://valtrinity.com/tools/unit-price-comparison-calculator/): Compare up to four products by price per kilo, per litre, per item or per metre, including multipacks and different units.
- [Cost Per Use Calculator](https://valtrinity.com/tools/cost-per-use-calculator/): See what something really costs each time you use it, with resale value and running costs, and compare two items.
- [Cashback Calculator](https://valtrinity.com/tools/cashback-calculator/): Work out how much cashback a card or scheme gives you a year after any cap and annual fee, and the spend needed to break even.
- [Multi-buy Deal Calculator](https://valtrinity.com/tools/multi-buy-deal-calculator/): See what 3 for 2, 2 for £3, buy one get one and half price offers really save, for the number you want to buy.
- [Subscription Cost Calculator](https://valtrinity.com/tools/subscription-cost-calculator/): Add up what weekly, monthly and yearly subscriptions cost you a month, a year and a day.
- [Tip Calculator](https://valtrinity.com/tools/tip-calculator/): Work out the tip, the total bill and each share, with optional rounding.
- [Discount Calculator](https://valtrinity.com/tools/discount-calculator/): Find a sale price, the effect of several discounts in a row, or the original price.
- [EV Charging Cost Calculator](https://valtrinity.com/tools/ev-charging-cost-calculator/): Work out what it costs to charge an electric car between two levels, the range added, the cost a mile and the time at your charger.
- [Tyre Size Calculator](https://valtrinity.com/tools/tyre-size-calculator/): Work out the sidewall, overall diameter and circumference of a tyre, and how a different size changes your speedometer.
- [Stopping Distance Calculator](https://valtrinity.com/tools/stopping-distance-calculator/): See the thinking, braking and total stopping distance for any speed, using the Highway Code figures, with wet and icy road estimates.
- [Electric vs Petrol Running Cost Calculator](https://valtrinity.com/tools/ev-vs-petrol-calculator/): Compare a year of fuel for a petrol or diesel car against an electric car, from your mileage, economy and the price of fuel and electricity.
- [Fuel Cost Calculator](https://valtrinity.com/tools/fuel-cost-calculator/): Estimate the fuel for a trip and its cost, using miles per gallon or litres per 100 km.
- [UK Degree to US GPA Converter](https://valtrinity.com/tools/gpa-converter/): Estimate a US GPA from a UK degree class or percentage, or a UK class from a GPA.
- [UK Degree Classification Calculator](https://valtrinity.com/tools/uk-degree-classification-calculator/): Turn your module marks and credits into a weighted average and a degree class, and see the average you need on the modules still to come.
- [UCAS Tariff Points Calculator](https://valtrinity.com/tools/ucas-tariff-points-calculator/): Add up UCAS Tariff points from A levels, AS levels, EPQ, Scottish Highers, BTEC Nationals and T Levels, using the 2026 tables.
- [Study Time Planner](https://valtrinity.com/tools/study-time-planner/): Share your revision hours between topics between today and the exam, using the days you can study and how heavy each topic is.
- [Test Score Percentage Calculator](https://valtrinity.com/tools/test-score-percentage-calculator/): Turn marks into a percentage for one test or several, and work out the marks needed on the next test to reach a target overall.
- [Times Tables Practice](https://valtrinity.com/tools/times-tables-practice/): Practise the times tables you choose against the clock and see which ones need more work.
- [Maths Worksheet Generator](https://valtrinity.com/tools/maths-worksheet-generator/): Make a printable arithmetic worksheet for a primary year group, with an answer key that matches.
- [Mental Maths Trainer](https://valtrinity.com/tools/mental-maths-trainer/): Quick-fire practice with number bonds, doubles, halves, rounding, percentages, fractions and squares.
- [Money Counting Practice](https://valtrinity.com/tools/money-counting-practice/): Count UK coins and work out change, with three levels from pence to pounds.
- [Clock Face Learning Tool](https://valtrinity.com/tools/clock-face-learning-tool/): Set the hands on an analogue clock, read the time in words and digits, or test yourself on reading the clock.
- [Number Line Generator](https://valtrinity.com/tools/number-line-generator/): Draw a number line with whole numbers, decimals or fractions, with missing labels and marked points, ready to print.
- [Fraction Wall Generator](https://valtrinity.com/tools/fraction-wall-generator/): Make a printable fraction wall with the rows you choose, and highlight any fraction to see its equivalents.
- [Column Method Calculator](https://valtrinity.com/tools/column-method-calculator/): See column addition, subtraction, long multiplication and short division written out step by step.
- [Revision Timetable Planner](https://valtrinity.com/tools/revision-timetable-planner/): Turn your subjects, exam dates and confidence into a day-by-day revision plan you can print.
- [Assignment Deadline Planner](https://valtrinity.com/tools/assignment-deadline-planner/): Break an essay, report or project into stages and see when each should start and finish before the deadline.
- [Reading Goal Calculator](https://valtrinity.com/tools/reading-goal-calculator/): Work out pages a day to finish a book by a date, when you will finish at your pace, or what a yearly book goal needs.
- [GPA Calculator](https://valtrinity.com/tools/gpa-calculator/): Work out your GPA on the US 4.0 scale, or your average for a UK degree classification.
- [Grade Calculator](https://valtrinity.com/tools/grade-calculator/): Work out your grade so far and the score you need on the final exam to reach a target.
- [Aspect Ratio Calculator](https://valtrinity.com/tools/aspect-ratio-calculator/): Find the aspect ratio of any size and work out a new width or height that keeps it.
- [Screen DPI and PPI Calculator](https://valtrinity.com/tools/screen-dpi-calculator/): Work out pixel density from a screen resolution and its size in inches.
- [Download Time Calculator](https://valtrinity.com/tools/download-time-calculator/): Estimate how long a file takes to download or upload at a given connection speed.
- [TV Size and Viewing Distance Calculator](https://valtrinity.com/tools/tv-size-viewing-distance-calculator/): Find the best viewing distance for a TV size and resolution, or the best TV size for the distance from your sofa.
- [Battery Life Calculator](https://valtrinity.com/tools/battery-life-calculator/): Work out how long a battery lasts for a given power draw, or what size of battery you need to run something for a set time.
- [Power Bank Charge Calculator](https://valtrinity.com/tools/power-bank-charge-calculator/): Find out how many times a power bank will charge your phone or tablet, allowing for conversion losses, and how long it takes to recharge.
- [Mobile Data Usage Calculator](https://valtrinity.com/tools/data-usage-calculator/): Estimate your monthly data use from the hours you stream, browse, game and call, and see whether it fits your plan.
- [RAID Capacity Calculator](https://valtrinity.com/tools/raid-capacity-calculator/): Work out the usable space and the drive failures survived for RAID 0, 1, 5, 6 and 10 from the number and size of your drives.
- [Odds Converter](https://valtrinity.com/tools/odds-converter/): Convert betting odds between fractional, decimal and American, and see the chance they imply.
- [Each Way Bet Calculator](https://valtrinity.com/tools/each-way-bet-calculator/): Work out the returns on an each way bet when the runner wins, places or loses, with an optional Rule 4 deduction.
- [Accumulator and Full Cover Bet Calculator](https://valtrinity.com/tools/accumulator-calculator/): Work out accumulator, Trixie, Yankee, Lucky 15, Heinz and other full cover bet returns from up to eight selections.
- [Dutching Calculator](https://valtrinity.com/tools/dutching-calculator/): Split a stake across several outcomes so each one returns the same amount, and see whether the total comes out ahead.
- [Overround and Margin Calculator](https://valtrinity.com/tools/overround-and-margin-calculator/): Add up the odds in a market to find the bookmaker's margin, and see fair odds with the margin taken out.
- [Golf Handicap Calculator (World Handicap System)](https://valtrinity.com/tools/golf-handicap-calculator/): Work out score differentials and a World Handicap System Handicap Index from up to 20 rounds, then a Course Handicap.
- [Stableford Points Calculator](https://valtrinity.com/tools/stableford-calculator/): Score a round of golf in Stableford points from your hole by hole scores, par, stroke index and handicap.
- [Cricket Run Rate Calculator](https://valtrinity.com/tools/cricket-run-rate-calculator/): Find the current run rate, the required run rate and the projected total in a limited overs cricket innings.
- [Cricket Batting and Bowling Average Calculator](https://valtrinity.com/tools/cricket-batting-and-bowling-average-calculator/): Calculate batting average, strike rate, bowling average and economy, and the runs needed to reach a target average.
- [Cricket Net Run Rate Calculator](https://valtrinity.com/tools/cricket-net-run-rate-calculator/): Calculate a team's net run rate over one or more matches, counting full overs when a side is bowled out.
- [Football League Table Generator](https://valtrinity.com/tools/football-league-table-generator/): Enter match results and get a sorted league table with points, goal difference and the tie-break rule you choose.
- [Round Robin Fixture Generator](https://valtrinity.com/tools/round-robin-fixture-generator/): Create a round robin schedule where every team plays every other team, with byes for odd numbers and home and away balance.
- [Tournament Bracket Generator](https://valtrinity.com/tools/tournament-bracket-generator/): Draw a single or double elimination bracket for 2 to 64 entrants, with seeding and byes, ready to print.
- [Darts Checkout Calculator](https://valtrinity.com/tools/darts-checkout-calculator/): Find the way to finish any score from 2 to 170 in darts, with every route and a full checkout chart.
- [Snooker Points Remaining Calculator](https://valtrinity.com/tools/snooker-points-remaining-calculator/): Work out the most points left on the table in a frame of snooker and whether the player behind needs snookers.
- [Tennis Score Tracker](https://valtrinity.com/tools/tennis-score-tracker/): Keep the score of a tennis match point by point, with games, sets, tie-breaks, deuce, the server and undo.
- [Ten-Pin Bowling Score Calculator](https://valtrinity.com/tools/bowling-score-calculator/): Score a game of ten-pin bowling frame by frame from your strikes, spares and misses, and see the best score still possible.
- [Cycling Gear Inches Calculator](https://valtrinity.com/tools/cycling-gear-inches-calculator/): Compare bicycle gears by gear inches, metres of travel per pedal turn and speed at your cadence.
- [Swimming Lengths Calculator](https://valtrinity.com/tools/swimming-lengths-calculator/): Convert between swimming distance and pool lengths in metres or yards, and work out your pace for each 100.
- [Chess Clock](https://valtrinity.com/tools/chess-clock/): A two player chess clock with increment or delay, common time controls, move counts and a flag when time runs out.
- [Elo Rating Calculator](https://valtrinity.com/tools/elo-rating-calculator/): Work out expected scores and your new Elo rating after one game or a whole event, with the K-factor you choose.
- [Scrabble Word Score Calculator](https://valtrinity.com/tools/scrabble-word-score-calculator/): Score a Scrabble word with letter values, double and triple letter and word squares, blanks and the seven tile bonus.
- [Poker Hand Odds Calculator](https://valtrinity.com/tools/poker-hand-odds-calculator/): Rank your poker hand and see your chance of winning against random opponents, and what you will make by the river.
- [Knitting Gauge Calculator](https://valtrinity.com/tools/knitting-gauge-calculator/): Work out how many stitches to cast on from your gauge, or convert a pattern to your own tension.
- [Guitar Chord Finder](https://valtrinity.com/tools/guitar-chord-finder/): Pick a chord and see open and barre shapes drawn as diagrams, with the frets and the notes in standard tuning.
- [Music Scale Finder](https://valtrinity.com/tools/music-scale-finder/): See the notes of any major, minor, mode, pentatonic or blues scale and the chords in it, or find scales that fit your notes.
- [Piano Chord Finder](https://valtrinity.com/tools/piano-chord-finder/): See any chord on a keyboard with its notes and inversions, or type notes to find out what chord they make.
- [Gravel, Topsoil and Bark Calculator](https://valtrinity.com/tools/garden-material-calculator/): Work out how much gravel, crushed stone, sand, topsoil or bark to order for a path, bed or drive, in cubic metres, tonnes and bags.
- [Lawn Turf and Grass Seed Calculator](https://valtrinity.com/tools/lawn-calculator/): Find out how many rolls of turf or how much grass seed a new lawn or a repair needs.
- [Raised Bed Soil Calculator](https://valtrinity.com/tools/raised-bed-calculator/): Work out the soil, compost and sand to fill raised beds, and the length of timber to build the sides.
- [Plant Spacing Calculator](https://valtrinity.com/tools/plant-spacing-calculator/): Count how many plants fit in a bed or hedge at a given spacing, in a square grid or a staggered layout.
- [Pond Liner Calculator](https://valtrinity.com/tools/pond-liner-calculator/): Find the size of liner for a garden pond from its length, width, depth and overlap, and an estimate of the water volume.

## Science and Engineering Calculators

- [Science and Engineering Calculators](https://valtrinity.com/science-calculators/): Use Ohm's law, work out power, force and energy, calculate molar mass and dilution, and solve speed, distance and time problems.
- [Ohm's Law Calculator](https://valtrinity.com/tools/ohms-law-calculator/): Enter any two of voltage, current, resistance and power and get the other two.
- [Voltage Divider Calculator](https://valtrinity.com/tools/voltage-divider-calculator/): Find the output voltage of two resistors in series, with an optional load.
- [Resistor Colour Code Calculator](https://valtrinity.com/tools/resistor-colour-code-calculator/): Read the value of a 4, 5 or 6 band resistor, or find the colours for a value.
- [Resistors in Series and Parallel Calculator](https://valtrinity.com/tools/resistors-in-series-and-parallel-calculator/): Add resistors in series and parallel from a list of values such as 4.7k and 220.
- [Capacitors in Series and Parallel Calculator](https://valtrinity.com/tools/capacitors-in-series-and-parallel-calculator/): Find the total capacitance of capacitors in series and parallel from a list of values.
- [LED Resistor Calculator](https://valtrinity.com/tools/led-resistor-calculator/): Find the series resistor for an LED from the supply, forward voltage and current.
- [Voltage Drop Calculator (UK Cable)](https://valtrinity.com/tools/voltage-drop-calculator/): Estimate the voltage drop of a copper cable run and check it against the 3% and 5% limits.
- [Battery Runtime Calculator](https://valtrinity.com/tools/battery-runtime-calculator/): Estimate how long a battery will run a load, allowing for usable capacity and efficiency.
- [RC Time Constant Calculator](https://valtrinity.com/tools/rc-time-constant-calculator/): Find the time constant, cut-off frequency and charging times for a resistor and capacitor.
- [Wire Resistance Calculator](https://valtrinity.com/tools/wire-resistance-calculator/): Find the resistance of a length of wire from its material, size and temperature.
- [Decibel Calculator](https://valtrinity.com/tools/decibel-calculator/): Convert between decibels and power or voltage ratios, and between dBm and milliwatts.
- [LC Resonant Frequency Calculator](https://valtrinity.com/tools/resonant-frequency-calculator/): Find the resonant frequency of an inductor and capacitor, with Q and bandwidth.
- [Electrical Power Calculator](https://valtrinity.com/tools/electrical-power-calculator/): Find watts, volts or amps for direct current, single phase or three phase, with power factor and running cost.
- [Inductive and Capacitive Reactance Calculator](https://valtrinity.com/tools/reactance-calculator/): Find the AC reactance of an inductor or a capacitor, and the impedance with a series resistor.
- [Transformer Calculator](https://valtrinity.com/tools/transformer-calculator/): Find the turns ratio, secondary voltage, turns and currents of a transformer.
- [Acceleration and SUVAT Calculator](https://valtrinity.com/tools/suvat-calculator/): Solve constant acceleration problems, including simple speed change over time, from any three of s, u, v, a and t.
- [Projectile Motion Calculator](https://valtrinity.com/tools/projectile-motion-calculator/): Find range, flight time and maximum height from launch speed, angle and height, including a simple drop.
- [Wavelength and Frequency Calculator](https://valtrinity.com/tools/wavelength-frequency-calculator/): Convert between wavelength and frequency for light, radio and sound, with photon energy.
- [Specific Heat Calculator](https://valtrinity.com/tools/specific-heat-calculator/): Find the heat needed to change a temperature, or solve for mass, specific heat or temperature change.
- [Half-Life Calculator](https://valtrinity.com/tools/half-life-calculator/): Find the amount remaining, time elapsed, half-life or starting amount for radioactive decay.
- [Pendulum Period Calculator](https://valtrinity.com/tools/pendulum-period-calculator/): Find the period and frequency of a pendulum from its length, with an allowance for wide swings.
- [Force Calculator](https://valtrinity.com/tools/force-calculator/): Solve for force, momentum, impulse, circular motion, gravity between masses or charge attraction.
- [Work, Energy and Power Calculator](https://valtrinity.com/tools/work-energy-power-calculator/): Solve kinetic energy, potential energy, work and power, or efficiency, filling in whichever value is missing.
- [Pressure and Density Calculator](https://valtrinity.com/tools/pressure-and-density-calculator/): Solve pressure, density, the pressure at depth in a fluid, or whether an object floats.
- [Orbital and Escape Velocity Calculator](https://valtrinity.com/tools/orbital-velocity-calculator/): Find the orbital speed, orbit time and escape speed at a height above a planet, moon or star.
- [Refraction and Snell's Law Calculator](https://valtrinity.com/tools/refraction-calculator/): Find the angle light bends when it passes between materials, and the critical angle.
- [Speed, Distance and Time Calculator](https://valtrinity.com/tools/speed-distance-time-calculator/): Solve for speed, distance or time, work out running pace and predict a race finish time.
- [Molar Mass Calculator](https://valtrinity.com/tools/molar-mass-calculator/): Work out the molar mass of any chemical formula, with the mass percent of each element.
- [Molarity Calculator](https://valtrinity.com/tools/molarity-calculator/): Find molarity, moles, volume, grams and number of particles for a solution, from a mass and formula or from moles.
- [Dilution Calculator (C1V1 = C2V2)](https://valtrinity.com/tools/dilution-calculator/): Find the volume of stock to use, the final concentration or final volume of a dilution.
- [pH Calculator](https://valtrinity.com/tools/ph-calculator/): Find pH, pOH and ion concentrations, including strong and weak acids and bases.
- [Ideal Gas Law Calculator](https://valtrinity.com/tools/ideal-gas-law-calculator/): Find pressure, volume, amount or temperature of a gas using PV = nRT.
- [Percent Yield Calculator](https://valtrinity.com/tools/percent-yield-calculator/): Find the percent yield of a reaction, and the theoretical yield from the limiting reactant.
- [Empirical Formula Calculator](https://valtrinity.com/tools/empirical-formula-calculator/): Find the empirical formula, and the molecular formula, from masses or percentages.
- [Periodic Table Explorer](https://valtrinity.com/tools/periodic-table-explorer/): An interactive periodic table with the name, atomic number, mass, group, period and state of all 118 elements.
- [Gear Ratio Calculator](https://valtrinity.com/tools/gear-ratio-calculator/): Find the gear ratio, output speed and output torque for one, two or three stages.
- [Torque Calculator](https://valtrinity.com/tools/torque-calculator/): Find torque from force and lever arm, or from power and rotational speed.
- [Stress and Strain Calculator](https://valtrinity.com/tools/stress-strain-calculator/): Find stress, strain, elongation and Young's modulus for a bar under load.
- [Dew Point Calculator](https://valtrinity.com/tools/dew-point-calculator/): Find the dew point from temperature and humidity, or the humidity from the dew point.
- [Thermal Expansion Calculator](https://valtrinity.com/tools/thermal-expansion-calculator/): Find how much a bar, pipe or beam grows or shrinks as the temperature changes.
- [Pipe Flow Velocity Calculator](https://valtrinity.com/tools/pipe-flow-calculator/): Find the flow rate, velocity or pipe diameter from the other two, with Reynolds number for water.
- [Feels Like Temperature (Wind Chill and Heat Index)](https://valtrinity.com/tools/feels-like-temperature-calculator/): Find how hot or cold it feels from temperature, wind and humidity: wind chill when cold, heat index when hot.

## Text Tools

- [Text Tools](https://valtrinity.com/text-tools/): Count words, change text case, generate placeholder copy, compare two versions of a document and sort or de-duplicate lists.
- [Readability Score Checker](https://valtrinity.com/tools/readability-score-checker/): See how easy your writing is to read, with a plain English verdict.
- [Online Text Editor](https://valtrinity.com/tools/online-text-editor/): Write with bold, italic, headings, lists and links, see a word count, and download as .txt, .html or .docx.
- [Grammar Checker](https://valtrinity.com/tools/grammar-checker/): Find spelling, grammar and punctuation mistakes, then accept the fixes one by one or all at once.
- [Paraphrasing Tool](https://valtrinity.com/tools/paraphrasing-tool/): Reword a passage in a standard, formal, simple, shorter or longer style.
- [Article Rewriter](https://valtrinity.com/tools/article-rewriter/): Rewrite an article or section of text in a neutral, formal, friendly or confident tone.
- [Text Summariser](https://valtrinity.com/tools/text-summarizer/): Shorten long text into bullet points or a short paragraph.
- [AI Writer](https://valtrinity.com/tools/ai-writer/): Draft an outline, blog post, product description, email or social post from a topic and your facts.
- [AI Humaniser](https://valtrinity.com/tools/ai-humanizer/): Rewrite stiff or repetitive text so it reads more naturally.
- [AI Content Detector](https://valtrinity.com/tools/ai-content-detector/): Get a rough estimate of how likely a text is to be machine written, with the signals behind it.
- [Plagiarism Checker](https://valtrinity.com/tools/plagiarism-checker/): Look up sentences from your text and see which web and encyclopedia pages contain similar wording.
- [Title Capitaliser](https://valtrinity.com/tools/title-capitaliser/): Capitalise a title in APA, Chicago or sentence style, or capitalise every word.
- [Essay Planner](https://valtrinity.com/tools/essay-planner/): Plan an essay paragraph by paragraph with a word budget that adds up to your limit.
- [Word Counter](https://valtrinity.com/tools/word-counter/): Count words, characters, sentences and reading time as you type.
- [Reading Time Calculator](https://valtrinity.com/tools/reading-time-calculator/): Estimate how long text takes to read silently or to say aloud, at speeds you choose.
- [Keyword Density Checker](https://valtrinity.com/tools/keyword-density-checker/): Count the words and phrases that appear most often in your text.
- [Word Frequency Counter](https://valtrinity.com/tools/word-frequency-counter/): Count how often each word appears, with each word's share of the text and a CSV download.
- [UTF-8 Byte Counter](https://valtrinity.com/tools/utf8-byte-counter/): Count the bytes in text, in UTF-8 and UTF-16, and see how many text messages it needs.
- [Speaking Time Calculator](https://valtrinity.com/tools/speaking-time-calculator/): Work out how long a speech or script takes to say, or how many words fit in the time you have.
- [Characters Per Line](https://valtrinity.com/tools/count-characters-per-line/): See how many characters and words each line has, and which lines go over a limit.
- [Character Frequency Counter](https://valtrinity.com/tools/character-frequency-counter/): Count how often each character appears, with percentages and a vowel and consonant total.
- [Case Converter](https://valtrinity.com/tools/case-converter/): Switch text between upper, lower, title, camelCase, snake_case and more.
- [Slug Generator](https://valtrinity.com/tools/slug-generator/): Turn a title or phrase into a clean, lowercase web address slug with your choice of separator.
- [Remove Line Breaks](https://valtrinity.com/tools/remove-line-breaks/): Join broken lines into flowing text, and keep paragraphs wherever you want them.
- [Find and Replace Text](https://valtrinity.com/tools/find-and-replace/): Find and replace text with options for capitals, whole words and patterns, plus a count of every change.
- [Remove Extra Spaces](https://valtrinity.com/tools/remove-extra-spaces/): Collapse double spaces, trim the edges of each line and remove blank lines in one step.
- [Emoji Remover](https://valtrinity.com/tools/emoji-remover/): Strip emoji from text and keep letters, numbers and ordinary symbols.
- [Whitespace Visualiser](https://valtrinity.com/tools/whitespace-visualiser/): Show spaces, tabs, line breaks and hidden characters in your text as visible marks.
- [HTML to Text Converter](https://valtrinity.com/tools/html-to-text/): Strip HTML tags and keep the readable text, with paragraphs and lists intact.
- [Add Line Numbers to Text](https://valtrinity.com/tools/add-line-numbers/): Put a number at the start of every line, or take numbers off again.
- [Invisible Character](https://valtrinity.com/tools/invisible-character/): Copy a blank or zero width character, and test text to see where invisible characters hide.
- [Text Cleaner](https://valtrinity.com/tools/text-cleaner/): Remove duplicate lines, blank lines, extra spaces, tabs, smart quotes and hidden characters in one go.
- [Line Formatter](https://valtrinity.com/tools/line-formatter/): Add text, quotes, bullets or numbers to every line, take them off again, or remove empty lines.
- [Remove Repeated Words](https://valtrinity.com/tools/remove-duplicate-words/): Remove repeated words, doubled words such as "the the", or common filler words from your text.
- [Word Wrap Tool](https://valtrinity.com/tools/word-wrap-tool/): Wrap long lines at a chosen width without cutting words, or join wrapped lines back together.
- [Text to HTML Paragraphs](https://valtrinity.com/tools/plain-text-to-html-paragraphs/): Turn plain text into HTML paragraphs with line breaks and optional links.
- [BBCode to HTML](https://valtrinity.com/tools/bbcode-to-html/): Convert forum BBCode tags such as b, url, quote, list and code to HTML.
- [Markdown Stripper](https://valtrinity.com/tools/markdown-stripper/): Remove Markdown symbols and leave clean plain text, keeping links as words or with their addresses.
- [Tabs to Spaces Converter](https://valtrinity.com/tools/tabs-to-spaces-converter/): Replace tabs with spaces that respect tab stops, or turn leading spaces into tabs.
- [Text Diff Checker](https://valtrinity.com/tools/text-diff/): Compare two texts and see added and removed lines side by side.
- [Sort Lines & Remove Duplicates](https://valtrinity.com/tools/text-sorter/): Sort a list A to Z, remove duplicate lines and tidy blank lines.
- [Text Repeater](https://valtrinity.com/tools/text-repeater/): Repeat a word, line or short passage a set number of times, with your choice of separator.
- [Reverse Text](https://valtrinity.com/tools/reverse-text/): Reverse text character by character, word by word or line by line.
- [Email Address Extractor](https://valtrinity.com/tools/email-extractor/): Pull every email address out of a block of text, with duplicates removed.
- [URL Extractor](https://valtrinity.com/tools/url-extractor/): List every web address found in your text, HTML or notes.
- [Comma Separator](https://valtrinity.com/tools/comma-separator/): Turn a list into one line separated by commas, or split a comma separated line back into a list.
- [Split Text](https://valtrinity.com/tools/split-text/): Break long text into parts by character count, words, lines or a chosen separator.
- [Text to Columns](https://valtrinity.com/tools/text-to-columns/): Arrange a list of lines into a chosen number of columns, ready to paste into a spreadsheet.
- [List Randomiser](https://valtrinity.com/tools/list-randomiser/): Shuffle the lines of a list into a random order, or pick one or more lines at random.
- [Word Sorter](https://valtrinity.com/tools/word-sorter/): Sort the words in a sentence or paragraph alphabetically, by length, or in reverse order.
- [Extract From Text](https://valtrinity.com/tools/extract-from-text/): Pull numbers, hashtags or @mentions out of any text, with totals for the numbers.
- [Compare Two Lists](https://valtrinity.com/tools/compare-two-lists/): Find what is only in list A, only in list B, in both, or in either, with counts.
- [Split Into Sentences](https://valtrinity.com/tools/split-into-sentences/): Put each sentence of a paragraph on its own line, without splitting at abbreviations or initials.
- [Lorem Ipsum Generator](https://valtrinity.com/tools/lorem-ipsum/): Generate placeholder paragraphs, sentences or words for mock-ups.
- [Fancy Text Generator](https://valtrinity.com/tools/fancy-text-generator/): Turn plain text into bold, italic, script, gothic and other fancy letter styles.
- [Palindrome Checker](https://valtrinity.com/tools/palindrome-checker/): Check whether a word or phrase reads the same backwards, and find the longest palindrome in any text.
- [Unicode Character Finder](https://valtrinity.com/tools/unicode-character-finder/): Look up the code point, UTF-8 bytes, category, script and block of any character.
- [Pig Latin Translator](https://valtrinity.com/tools/pig-latin-translator/): Translate English into Pig Latin, keeping capitals and punctuation.
- [Small Text Generator](https://valtrinity.com/tools/small-text-generator/): Turn your words into small caps, superscript, subscript, bubble and square text, each with its own copy button.
- [Lorem Ipsum Styles](https://valtrinity.com/tools/lorem-ipsum-styles/): Placeholder text in Latin, plain English, business, technology and food styles, as text or HTML.
- [Text Effects Generator](https://valtrinity.com/tools/text-effects-generator/): Turn your text into alternating case, mirror text, zalgo glitch text, underlines, leetspeak and more.
- [Character Converter](https://valtrinity.com/tools/character-converter/): Remove punctuation or accents, curl or straighten quotes, normalise Unicode and switch full width letters.
- [Acronym Generator](https://valtrinity.com/tools/acronym-generator/): Make an acronym or set of initials from a phrase, with or without small words like of and the.
- [Anagram Checker](https://valtrinity.com/tools/anagram-checker/): Check whether two words or phrases are anagrams, and see the letters that differ.
- [Morse Code Translator](https://valtrinity.com/tools/morse-code-translator/): Translate text into Morse code and Morse code back into text.
- [Caesar Cipher Tool](https://valtrinity.com/tools/caesar-cipher/): Shift letters forwards or backwards with a Caesar cipher, including ROT13.
- [NATO Phonetic Alphabet Converter](https://valtrinity.com/tools/nato-phonetic-alphabet/): Spell out text with the NATO alphabet, or turn code words back into letters.
- [ROT13 and Simple Ciphers](https://valtrinity.com/tools/rot13-encoder/): Encode and decode ROT13, ROT5, ROT47, Atbash, A1Z26 and affine ciphers.
- [Vigenere Cipher](https://valtrinity.com/tools/vigenere-cipher/): Encode and decode text with the Vigenere cipher using a keyword.
- [Rail Fence Cipher](https://valtrinity.com/tools/rail-fence-cipher/): Encode and decode the rail fence zigzag transposition cipher with any number of rails.
- [Number to Words Converter](https://valtrinity.com/tools/number-to-words/): Write numbers in words, UK style, or turn an amount into cheque wording in pounds and pence.
- [Citation Generator](https://valtrinity.com/tools/citation-generator/): Build APA 7, MLA 9, Harvard, Chicago, IEEE and Vancouver citations for websites, books, articles and videos.
- [Spelling Test Maker](https://valtrinity.com/tools/spelling-test-maker/): Enter a word list, hear each word read aloud, type it, and see which ones to practise.
- [Bibliography Sorter](https://valtrinity.com/tools/bibliography-sorter/): Sort a reference list into alphabetical order, remove duplicates and numbering, and keep same-author works in date order.
- [British and American Spelling Converter](https://valtrinity.com/tools/british-american-spelling-converter/): Convert text between British and American spelling, and see every change and the words to check by hand.
- [Verb Conjugation Tables](https://valtrinity.com/tools/verb-conjugation-tables/): See French, Spanish and German verbs in the main tenses, for regular verbs and the most common irregular ones.
- [French, Spanish and German Numbers](https://valtrinity.com/tools/french-spanish-german-numbers/): Write any number up to 999,999,999 in words in French, Spanish and German.
- [Typing Practice Lessons](https://valtrinity.com/tools/typing-practice-lessons/): Work through typing lessons from the home row to sentences, with accuracy and the keys you get wrong.
- [Phone Number Formatter](https://valtrinity.com/tools/phone-number-formatter/): Format UK and international phone numbers as national, international or E.164.
- [UK Postcode Validator](https://valtrinity.com/tools/uk-postcode-validator/): Check UK postcodes for the right format and tidy them to the standard layout.
- [ISBN Validator and Converter](https://valtrinity.com/tools/isbn-validator/): Check ISBN-10 and ISBN-13 numbers and convert between the two forms.

## Developer Tools

- [Developer Tools](https://valtrinity.com/developer-tools/): Format JSON, convert JSON to CSV and CSV to JSON, encode Base64, test regular expressions, convert Unix timestamps, create UUIDs and generate hashes.
- [JSON Formatter & Validator](https://valtrinity.com/tools/json-formatter/): Pretty-print, minify and validate JSON with clear error messages.
- [HTML Minifier](https://valtrinity.com/tools/html-minifier/): Shrink HTML by removing comments and extra whitespace, with the size saved shown.
- [CSS Formatter](https://valtrinity.com/tools/css-formatter/): Beautify CSS with tidy indentation, one declaration per line and your choice of style.
- [JavaScript Formatter](https://valtrinity.com/tools/javascript-formatter/): Beautify JavaScript with consistent indentation, spacing and line breaks.
- [Markdown Previewer](https://valtrinity.com/tools/markdown-previewer/): Write Markdown and see a live preview, then copy the matching HTML.
- [JSON Key Sorter](https://valtrinity.com/tools/json-sort-keys/): Sort the keys of a JSON object alphabetically, naturally or ignoring case, at every level, without changing any values.
- [SQL Formatter](https://valtrinity.com/tools/sql-formatter/): Tidy SQL queries with clean indents, line breaks and keyword case.
- [CSS Minifier & Beautifier](https://valtrinity.com/tools/css-minifier/): Shrink CSS for faster pages, or spread it out so it is easy to read.
- [JavaScript Minifier](https://valtrinity.com/tools/javascript-minifier/): Strip comments and spaces from JavaScript and see the size saved.
- [HTML Formatter & Minifier](https://valtrinity.com/tools/html-formatter/): Indent messy HTML for reading, or compact it to cut page weight.
- [XML Formatter & Validator](https://valtrinity.com/tools/xml-formatter/): Pretty print or minify XML and check it is well formed.
- [CSV Viewer](https://valtrinity.com/tools/csv-viewer/): Open a CSV as a table you can sort, filter and summarise.
- [CSV Cleaner](https://valtrinity.com/tools/csv-cleaner/): Tidy a messy CSV: trim spaces, drop empty rows and columns, straighten curly quotes and clear out hidden characters.
- [CSV Duplicate Remover](https://valtrinity.com/tools/csv-deduplicator/): Remove duplicate rows from a CSV using the columns you choose, or list only the rows that repeat.
- [CSV Column Extractor and Reorder](https://valtrinity.com/tools/csv-column-extractor/): Keep only the columns you need, put them in a new order and rename them.
- [CSV Merge](https://valtrinity.com/tools/csv-merge/): Stack several CSV files into one table, lining the columns up by name.
- [Join Two Tables on a Key Column](https://valtrinity.com/tools/csv-join-tables/): Match two tables on a shared column and bring across the columns you want, like a look-up.
- [CSV Splitter](https://valtrinity.com/tools/csv-splitter/): Split a large CSV into smaller files by number of rows, number of files or the values in a column.
- [CSV Sorter](https://valtrinity.com/tools/csv-sorter/): Sort a CSV by up to three columns, as text, numbers or dates, in either direction.
- [CSV Filter](https://valtrinity.com/tools/csv-filter/): Keep or remove the rows of a CSV that meet conditions you set, using text, numbers or dates.
- [Pivot Table Maker](https://valtrinity.com/tools/pivot-table-maker/): Summarise a table by one or two fields: totals, counts, averages, smallest and largest.
- [Unpivot Table (Wide to Long)](https://valtrinity.com/tools/unpivot-table/): Turn columns such as Jan, Feb and Mar into rows, so the table is ready for pivot tables and charts.
- [CSV Column Statistics](https://valtrinity.com/tools/csv-summary-statistics/): Profile every column of a CSV: type, blanks, different values, sum, mean, median, smallest and largest.
- [CSV to Excel Converter](https://valtrinity.com/tools/csv-to-excel/): Turn a CSV into a proper .xlsx workbook with real numbers, dates, a bold header, filters and sensible column widths.
- [Excel to CSV Converter](https://valtrinity.com/tools/excel-to-csv/): Open an .xlsx workbook, pick a sheet and save it as CSV or TSV with dates written as dates.
- [Excel Column Letter Converter](https://valtrinity.com/tools/excel-column-letter-converter/): Change column letters to numbers and numbers to letters, for example A to 1, Z to 26, AA to 27 and 16384 to XFD.
- [Excel Date Serial Number Converter](https://valtrinity.com/tools/excel-date-serial-converter/): Turn Excel date serial numbers such as 45000 into dates, and dates back into serial numbers.
- [CSV Delimiter Converter](https://valtrinity.com/tools/delimiter-converter/): Change a file between comma, semicolon, tab and pipe separators, with control over quoting, line endings and decimal marks.
- [CSV Validator](https://valtrinity.com/tools/csv-validator/): Check a CSV for unclosed quotes, rows with the wrong number of values, bad characters and other faults, with line numbers.
- [Transpose Table](https://valtrinity.com/tools/transpose-table/): Swap the rows and columns of a table so that rows become columns and columns become rows.
- [CSV Find and Replace by Column](https://valtrinity.com/tools/csv-find-and-replace/): Replace values in chosen columns of a CSV with up to four rules, including whole-cell and pattern matches.
- [Data Anonymiser](https://valtrinity.com/tools/data-anonymiser/): Hide names, emails, phone numbers and other personal details in a table before you share it.
- [Random Sample of Rows](https://valtrinity.com/tools/random-sample-of-rows/): Pick a random sample of rows from a CSV by number or percentage, optionally from each group, with a seed for repeatable results.
- [Chart Maker from Pasted Data](https://valtrinity.com/tools/chart-maker/): Make bar, stacked bar, line, pie and donut charts from a pasted table and download them as PNG or SVG.
- [Fixed Width to CSV Converter](https://valtrinity.com/tools/fixed-width-to-csv/): Convert fixed width text, where columns line up in neat blocks, into a CSV by finding the gaps or setting positions.
- [CSV Column Calculator](https://valtrinity.com/tools/csv-column-calculator/): Add a new column worked out from a formula, such as Price * Quantity, with if, round, text and date functions.
- [Compare Two CSV Files](https://valtrinity.com/tools/csv-compare/): See what changed between two versions of a table: rows added, removed and cells changed, matched on a key column.
- [Split a Column into Several Columns](https://valtrinity.com/tools/split-column-into-columns/): Split one column into several at a comma, space, dash or fixed width, the way text to columns does in a spreadsheet.
- [CSV Date and Number Fixer](https://valtrinity.com/tools/csv-date-and-number-fixer/): Make dates and numbers in a CSV consistent: one date format, plain numbers without £, commas or brackets.
- [CSV Value Counter](https://valtrinity.com/tools/csv-value-counts/): Count how many times each value appears in a column, with percentages, or group numbers into ranges.
- [Fill Blank Cells in a CSV](https://valtrinity.com/tools/fill-blank-cells/): Fill empty cells with the value above or below, a fixed value, or the mean, median or most common value of the column.
- [JSON to CSV Converter](https://valtrinity.com/tools/json-to-csv/): Turn a JSON array into a CSV table you can open in a spreadsheet.
- [CSV to JSON Converter](https://valtrinity.com/tools/csv-to-json/): Convert CSV rows into a clean JSON array of objects.
- [SQL INSERT to JSON Converter](https://valtrinity.com/tools/sql-to-json/): Turn SQL INSERT statements into JSON objects, one per row.
- [JSON to TypeScript Converter](https://valtrinity.com/tools/json-to-typescript/): Generate TypeScript interfaces or types from a sample of JSON.
- [CSV to SQL INSERT Converter](https://valtrinity.com/tools/csv-to-sql/): Turn CSV rows into SQL INSERT statements, with an optional CREATE TABLE.
- [JSON XML Converter](https://valtrinity.com/tools/json-xml-converter/): Convert JSON to XML or XML to JSON, with attributes, repeated elements and line numbers for errors.
- [CSV XML Converter](https://valtrinity.com/tools/csv-xml-converter/): Turn CSV rows into XML records, or flatten repeating XML records into a CSV table.
- [JSON to Code Converter](https://valtrinity.com/tools/json-to-code/): Generate Go structs, Python dataclasses or C# classes from a JSON sample, with optional fields worked out for you.
- [curl Converter](https://valtrinity.com/tools/curl-converter/): Convert a curl command into fetch, Python requests or axios code.
- [Config File Converter](https://valtrinity.com/tools/config-file-converter/): Convert between JSON, TOML, INI and .env files, with line numbers for any mistakes.
- [JSON Flattener](https://valtrinity.com/tools/json-flattener/): Flatten nested JSON into single-level keys such as user.address.city, or rebuild the nested form from flat keys.
- [JSON Lines Converter](https://valtrinity.com/tools/jsonl-converter/): Convert JSON Lines (one JSON value per line) to a JSON array, or an array to JSON Lines.
- [Query String to JSON Converter](https://valtrinity.com/tools/query-string-to-json/): Parse a URL query string into JSON with repeated and bracketed keys, or build a query string from JSON.
- [YAML and JSON Converter](https://valtrinity.com/tools/yaml-json-converter/): Convert YAML to JSON and JSON to YAML, with clear line-numbered errors.
- [Base64 Encode & Decode](https://valtrinity.com/tools/base64/): Encode text to Base64 or decode it back, with URL-safe output.
- [Text to Binary Converter](https://valtrinity.com/tools/text-to-binary/): Convert text to binary, hexadecimal, decimal or octal numbers and back again.
- [Regex Escaper](https://valtrinity.com/tools/regex-escaper/): Escape text so a regular expression matches it exactly, or undo the escaping.
- [Base32 Encoder and Decoder](https://valtrinity.com/tools/base32-converter/): Encode text to Base32 or decode it back, with standard, hex and Crockford alphabets.
- [ASCII Table](https://valtrinity.com/tools/ascii-table/): Look up ASCII codes in decimal, hex, octal and binary, with search.
- [SVG to Data URI Converter](https://valtrinity.com/tools/svg-to-data-uri/): Turn SVG code into a CSS-ready data URI, as encoded text or Base64.
- [URL Encoder & Decoder](https://valtrinity.com/tools/url-encoder-decoder/): Encode or decode URLs and query values, and break a web address into its parts.
- [HTML Entity Encoder & Decoder](https://valtrinity.com/tools/html-entity-encoder/): Convert special characters to HTML entities, and turn entities back into ordinary text.
- [String Escape and Unescape](https://valtrinity.com/tools/string-escape-unescape/): Escape or unescape text for JSON, JavaScript, Python, Java, C#, SQL, MySQL, CSV and shell strings.
- [Line Ending and Tab Converter](https://valtrinity.com/tools/line-ending-and-tab-converter/): Convert Windows, Unix and old Mac line endings, and change tabs to spaces or spaces to tabs, in text or a file.
- [Base58 Encoder and Decoder](https://valtrinity.com/tools/base58-encoder-decoder/): Encode text or hex to Base58 and decode it back, with the Bitcoin, Flickr and Ripple alphabets and Base58Check.
- [Punycode Converter](https://valtrinity.com/tools/punycode-converter/): Convert internationalised domain names to xn-- Punycode and back, in domains, URLs and email addresses.
- [Text Encoding Converter](https://valtrinity.com/tools/text-encoding-converter/): Convert text to hex, a hex dump, Unicode escapes or quoted-printable, and back.
- [UUID Generator](https://valtrinity.com/tools/uuid-generator/): Generate random v4 UUIDs in bulk, with format options.
- [Hash Generator](https://valtrinity.com/tools/hash-generator/): Create SHA-1, SHA-256, SHA-384 and SHA-512 hashes of text or files.
- [JWT Generator](https://valtrinity.com/tools/jwt-generator/): Create a signed HS256 JSON Web Token from your payload and a secret.
- [UUID Validator](https://valtrinity.com/tools/uuid-validator/): Check UUIDs and see their version, variant and creation time where it is stored.
- [JWT Decoder](https://valtrinity.com/tools/jwt-decoder/): Read the header, payload and expiry times of a JSON Web Token. The signature is not checked.
- [HMAC Generator](https://valtrinity.com/tools/hmac-generator/): Create an HMAC signature of a message with SHA-256, SHA-512, SHA-1, SHA-384 or MD5.
- [Checksum Calculator](https://valtrinity.com/tools/checksum-calculator/): Work out CRC-32, CRC-16, Adler-32, MD5, SHA-1 and SHA-256 of text, hex bytes or a file, and compare with a published value.
- [Bcrypt Hash Generator](https://valtrinity.com/tools/bcrypt-generator/): Create a bcrypt password hash with the cost you choose, or check whether a password matches a bcrypt hash.
- [Random ID and String Generator](https://valtrinity.com/tools/random-id-generator/): Generate ULIDs, NanoID style identifiers or random strings from any characters, and decode a ULID back to its time.
- [HTTP Header Parser](https://valtrinity.com/tools/http-header-parser/): Break raw HTTP headers into a readable list, with cache, cookie and type details.
- [URL Parser](https://valtrinity.com/tools/url-parser/): Split a web address into protocol, host, port, path, query and fragment.
- [CIDR and Subnet Calculator](https://valtrinity.com/tools/cidr-subnet-calculator/): Work out the network, broadcast, mask and usable range of an IPv4 subnet.
- [HTTP Status Codes Reference](https://valtrinity.com/tools/http-status-codes/): Search the common HTTP status codes, with a plain explanation of each and when to use it.
- [User Agent Parser](https://valtrinity.com/tools/user-agent-parser/): Read a user agent string to find the browser, its version, the operating system and the device.
- [IP Address Converter](https://valtrinity.com/tools/ip-address-converter/): Convert an IPv4 or IPv6 address between dotted, decimal, hex, binary, compressed and expanded forms.
- [IP Range to CIDR Converter](https://valtrinity.com/tools/ip-range-to-cidr/): Turn a start and end address into the smallest list of CIDR blocks that covers exactly that range.
- [MAC Address Formatter](https://valtrinity.com/tools/mac-address-formatter/): Reformat MAC addresses with colons, hyphens, dots or no separator, upper or lower case, and see the details.
- [MIME Type Lookup](https://valtrinity.com/tools/mime-type-lookup/): Find the media type for a file extension, or the extensions for a media type, with its registry status.
- [Common Ports Lookup](https://valtrinity.com/tools/common-ports-lookup/): Look up which service uses a network port, or which port a service uses, from a checked list of about a hundred.
- [Regex Tester](https://valtrinity.com/tools/regex-tester/): Test regular expressions with live match highlighting.
- [JSON Schema Validator](https://valtrinity.com/tools/json-schema-validator/): Check JSON data against a schema and see each problem with its path.
- [Side by Side Diff](https://valtrinity.com/tools/side-by-side-diff/): Compare two versions of code or text in two columns with line numbers and highlighted changes.
- [JSONPath Tester](https://valtrinity.com/tools/json-path-tester/): Try a JSONPath query against your JSON and see every match with its exact path.
- [Semver Comparator](https://valtrinity.com/tools/semver-comparator/): Compare, sort and bump semantic versions, and test which versions satisfy a range such as ^1.2.3 or ~2.0.
- [JSON Diff](https://valtrinity.com/tools/json-diff/): Compare two JSON documents and list what was added, removed or changed.
- [Unix Timestamp Converter](https://valtrinity.com/tools/timestamp-converter/): Convert Unix timestamps to readable dates and back.
- [Cron Expression Generator](https://valtrinity.com/tools/cron-expression-generator/): Build a cron schedule from simple choices and see it in plain English with the next five run times.
- [Cron Expression Explainer](https://valtrinity.com/tools/cron-expression-explainer/): Turn a five-field cron schedule into plain English and see its next five run times.
- [chmod Calculator](https://valtrinity.com/tools/chmod-calculator/): Tick the permissions you want and read the octal and symbolic chmod values, or type a value to see what it allows.
- [HTML Table Generator](https://valtrinity.com/tools/html-table-generator/): Paste spreadsheet or CSV data and get clean, accessible HTML table code with a live preview.
- [Gitignore Generator](https://valtrinity.com/tools/gitignore-generator/): Pick your languages, editors and systems and get a combined .gitignore file with sensible patterns.
- [Bitwise Calculator](https://valtrinity.com/tools/bitwise-calculator/): Apply AND, OR, XOR, NOT, shifts and rotations to numbers of 8 to 64 bits and see hex, decimal, signed and binary results.

## Create and Convert Tools

- [Create and Convert Tools](https://valtrinity.com/convert-and-create-tools/): Make QR codes, compress images, build CSS gradients and shadows, read QR codes and barcodes, and turn speech or video into text.
- [CSS Gradient Generator](https://valtrinity.com/tools/css-gradient-generator/): Create linear, radial or conic CSS gradients with up to five colour stops and copy the code.
- [Box Shadow Generator](https://valtrinity.com/tools/box-shadow-generator/): Layer soft or sharp box shadows, add inset shadows and copy the CSS with a live preview.
- [Border Radius Generator](https://valtrinity.com/tools/border-radius-generator/): Round each corner of a box by its own amount, see the result and copy the border-radius CSS.
- [Glassmorphism Generator](https://valtrinity.com/tools/glassmorphism-generator/): Create a frosted glass card with backdrop blur, tint and border, then copy the CSS.
- [CSS Clamp Calculator](https://valtrinity.com/tools/css-clamp-calculator/): Work out a clamp() value that scales font size or spacing smoothly between two screen widths.
- [PX to REM Converter](https://valtrinity.com/tools/px-rem-converter/): Convert between px, rem, em, vw and pt with a base font size, and see a conversion table.
- [CSS Text Shadow Generator](https://valtrinity.com/tools/css-text-shadow-generator/): Design a text shadow or glow with a live preview and copy the CSS.
- [Flexbox Playground](https://valtrinity.com/tools/flexbox-playground/): Change flex container and item settings and watch the boxes move, then copy the CSS and HTML.
- [CSS Grid Generator](https://valtrinity.com/tools/css-grid-generator/): Build a grid layout with fixed, flexible or custom columns and copy the CSS and HTML.
- [Clip Path Maker](https://valtrinity.com/tools/clip-path-maker/): Cut an element into a polygon, star, circle or ellipse and drag the points to reshape it.
- [Cubic Bezier Easing Editor](https://valtrinity.com/tools/cubic-bezier-easing-editor/): Drag the curve handles to design easing, watch a ball move with it and copy the timing function.
- [CSS Keyframes Builder](https://valtrinity.com/tools/css-animation-keyframes-builder/): Choose a motion, tune its strength and timing, and copy the @keyframes and animation rule.
- [CSS Pattern Generator](https://valtrinity.com/tools/css-pattern-generator/): Make stripes, dots, checks, grids and zigzags with pure CSS gradients, and copy the code.
- [Neumorphism Generator](https://valtrinity.com/tools/neumorphism-generator/): Create soft raised, pressed and curved surfaces with paired light and dark shadows.
- [CSS Button Generator](https://valtrinity.com/tools/css-button-generator/): Design a button with hover, active and focus states, check its contrast and copy the CSS and HTML.
- [CSS Triangle Generator](https://valtrinity.com/tools/css-triangle-generator/): Draw a triangle in eight directions using the border trick or clip-path, and copy the CSS.
- [CSS Filter Playground](https://valtrinity.com/tools/css-filter-playground/): Combine blur, brightness, contrast, hue and more on a picture and copy the filter property.
- [CSS Specificity Calculator](https://valtrinity.com/tools/css-specificity-calculator/): Score selectors by IDs, classes and elements, rank them and see which one wins.
- [Media Query Builder](https://valtrinity.com/tools/media-query-builder/): Build a media query from width, height, colour scheme, motion, pointer and more, and test it live.
- [CSS Cursor Tester](https://valtrinity.com/tools/css-cursor-tester/): Try every standard cursor value by pointing at it, see what each one means and copy the CSS.
- [Scrollbar Styler](https://valtrinity.com/tools/scrollbar-styler/): Style a scrollbar with colours, width and rounded corners, using the standard or the prefixed method.
- [CSS Transform Generator](https://valtrinity.com/tools/css-transform-generator/): Move, rotate, scale, skew and tilt an element in 3D, see it against its original place and copy the CSS.
- [CSS Loader Generator](https://valtrinity.com/tools/css-loader-generator/): Make a loading spinner, bouncing dots, rising bars or a pulse in pure CSS and copy the HTML and CSS.
- [CSS Underline and Text Decoration Generator](https://valtrinity.com/tools/css-text-decoration-generator/): Style underlines, overlines and strike-throughs with wavy or dotted lines, colour, thickness and offset.
- [SVG Wave Generator](https://valtrinity.com/tools/svg-wave-generator/): Make a wave divider as SVG, with smooth or rough edges, and copy it as SVG or as a CSS background.
- [SVG Blob Generator](https://valtrinity.com/tools/svg-blob-generator/): Create organic blob shapes as SVG paths, repeatable from a seed, and copy the code.
- [Font Pairing Previewer](https://valtrinity.com/tools/font-pairing-previewer/): Compare heading and body font stacks that are already on most computers, then copy the CSS.
- [Type Scale Generator](https://valtrinity.com/tools/type-scale-generator/): Build a modular type scale from a base size and ratio, with pixel and rem sizes and CSS variables.
- [Spacing Scale Generator](https://valtrinity.com/tools/spacing-scale-generator/): Turn a base unit into a spacing scale in px and rem, as straight steps, doubling or Fibonacci.
- [SVG Path Visualiser](https://valtrinity.com/tools/svg-path-editor-visualiser/): Paste path data to see the shape, its points and curve handles, and get a tidy absolute version.
- [Colour Palette Generator](https://valtrinity.com/tools/colour-palette-generator/): Build a matching colour palette from one base colour, then copy the codes or export CSS variables.
- [Colour Contrast Checker](https://valtrinity.com/tools/contrast-checker/): Check the contrast ratio between two colours against WCAG 2.2 and get a nearby colour that passes.
- [Colour Shades Generator](https://valtrinity.com/tools/colour-shades-generator/): Turn one colour into eleven tints and shades from 50 to 950, with contrast scores for text.
- [Colour Mixer](https://valtrinity.com/tools/colour-mixer/): Mix two colours in any proportion, see the steps between them and copy the colour-mix() code.
- [Text on Image Legibility Checker](https://valtrinity.com/tools/text-on-image-legibility-checker/): Check whether text stays readable over a photo, and how dark an overlay it needs.
- [Colour Name Finder](https://valtrinity.com/tools/colour-name-finder/): Find the closest of the 148 named CSS colours to any hex code, or look names up by their letters.
- [Text to Speech](https://valtrinity.com/tools/text-to-speech/): Read text aloud in the voice, speed, pitch and volume you choose.
- [Speech to Text](https://valtrinity.com/tools/speech-to-text/): Dictate with your voice, see the words appear live, then copy or download them as text.
- [Audio Trimmer](https://valtrinity.com/tools/audio-trimmer/): Cut a sound file to the part you want, with fades, and download it as a WAV file.
- [Audio to WAV Converter](https://valtrinity.com/tools/audio-to-wav-converter/): Convert MP3, M4A, OGG, FLAC or the sound of a video to a WAV file, with a choice of sample rate and channels.
- [Audio Volume Booster](https://valtrinity.com/tools/audio-volume-booster/): Make a quiet recording louder, or quieter, by a set number of decibels, with a limiter to stop crackle.
- [Audio Speed Changer](https://valtrinity.com/tools/audio-speed-changer/): Speed up or slow down a recording, keeping the pitch or letting it change with the speed.
- [Reverse Audio](https://valtrinity.com/tools/reverse-audio/): Play a sound backwards. Reverse a whole recording or just a chosen part and save it as a WAV file.
- [Audio Waveform Viewer](https://valtrinity.com/tools/audio-waveform-viewer/): Draw the waveform of a sound file and see its length, loudness, peaks and clipping at a glance.
- [Voice Recorder](https://valtrinity.com/tools/voice-recorder/): Record your voice from a microphone, pause and resume, play it back and download it.
- [Tone Generator](https://valtrinity.com/tools/tone-generator/): Play a pure tone at any frequency from 20 Hz to 20,000 Hz and download it as a WAV file.
- [Online Metronome](https://valtrinity.com/tools/metronome/): Keep time with an accurate metronome from 20 to 300 beats a minute, with accents and beats per bar.
- [BPM Tapper](https://valtrinity.com/tools/bpm-tapper/): Tap along to a song to find its tempo in beats per minute.
- [Online Guitar Tuner](https://valtrinity.com/tools/guitar-tuner/): Tune a guitar, bass, ukulele or violin by ear with a microphone, a needle and reference notes.
- [Microphone Test](https://valtrinity.com/tools/microphone-test/): Check that your microphone works, see its live level and play back a five second recording.
- [Video Transcriber](https://valtrinity.com/tools/video-transcriber/): Upload a video or audio file and get a timestamped transcript, with TXT, SRT and VTT downloads.
- [Video to MP3](https://valtrinity.com/tools/video-to-mp3/): Take the sound from a video and save it as an MP3 file, or as WAV.
- [Video Compressor](https://valtrinity.com/tools/video-compressor/): Re-save a video at a smaller size and resolution, with the sizes before and after.
- [SRT to VTT Converter](https://valtrinity.com/tools/srt-to-vtt-converter/): Convert subtitle files between SRT and VTT, and shift every caption earlier or later.
- [Screen Recorder](https://valtrinity.com/tools/screen-recorder/): Record your screen, a window or a browser tab, with sound where available, and download the video.
- [Webcam Test](https://valtrinity.com/tools/webcam-test/): Check your webcam works, see its resolution and frame rate, try other cameras and take a photo.
- [Webcam Recorder](https://valtrinity.com/tools/webcam-recorder/): Record a video from your webcam, with sound and a countdown, and download it.
- [Video to Frames](https://valtrinity.com/tools/video-to-frames/): Pull still pictures out of a video at set gaps, an exact number of frames or any moment you choose.
- [Video Info Viewer](https://valtrinity.com/tools/video-info-viewer/): See the length, picture size, shape, average data rate and frame rate of any video file.
- [QR Code Generator](https://valtrinity.com/tools/qr-code/): Make a QR code for any link or text and download it as a PNG.
- [CSV to Markdown Table](https://valtrinity.com/tools/csv-to-markdown-table/): Turn CSV or spreadsheet cells into a Markdown table with alignment.
- [HTML to Markdown Converter](https://valtrinity.com/tools/html-to-markdown/): Convert HTML into clean Markdown with headings, lists, links and tables.
- [QR Code Reader](https://valtrinity.com/tools/qr-code-reader/): Read a QR code from a picture and see what it says.
- [Barcode Reader](https://valtrinity.com/tools/barcode-reader/): Read a barcode from a picture. Supports EAN, UPC, Code 128, Code 39 and more.
- [JPG to Word Converter](https://valtrinity.com/tools/jpg-to-word/): Read the English text in a JPG or PNG picture and save it as an editable Word document.

## PDF and File Tools

- [PDF and File Tools](https://valtrinity.com/pdf-tools/): Merge PDF files, split a PDF or extract pages, and turn images into a PDF.
- [Unlock PDF](https://valtrinity.com/tools/unlock-pdf/): Open a password-protected PDF with its password and save a copy without the password.
- [Crop PDF](https://valtrinity.com/tools/crop-pdf/): Trim the margins off every page of a PDF, or just the pages you choose, in millimetres.
- [Add Blank Pages to PDF](https://valtrinity.com/tools/add-blank-pages-to-pdf/): Insert blank pages at the start, end, after a page or every few pages, or pad to an even count for double sided printing.
- [Resize PDF Pages](https://valtrinity.com/tools/resize-pdf-pages/): Change every page of a PDF to A4, A3, A5, Letter or Legal, scaling the content to fit.
- [Add Header and Footer to PDF](https://valtrinity.com/tools/add-header-footer-to-pdf/): Put text in the header or footer of every page, with page numbers, the date and the file name filled in for you.
- [Add an Image to PDF](https://valtrinity.com/tools/add-image-to-pdf/): Place a logo, stamp or signature picture on every page of a PDF or on the pages you choose.
- [Fill in a PDF Form](https://valtrinity.com/tools/fill-pdf-form/): Type into the text boxes, tick the boxes and choose from the lists of a fillable PDF, and flatten it if you wish.
- [Rotate PDF Pages](https://valtrinity.com/tools/rotate-pdf/): Turn all the pages of a PDF, or just the ones you pick, by 90, 180 or 270 degrees.
- [Add Page Numbers to PDF](https://valtrinity.com/tools/add-page-numbers-to-pdf/): Number the pages of a PDF in any corner or edge, with your own format and start number.
- [Add a Watermark to PDF](https://valtrinity.com/tools/watermark-pdf/): Stamp text such as DRAFT or CONFIDENTIAL across the pages of a PDF.
- [Sign a PDF](https://valtrinity.com/tools/sign-pdf/): Draw or type your signature and place it on any page of a PDF.
- [PDF Metadata Editor](https://valtrinity.com/tools/pdf-metadata-editor/): See and change the title, author, subject and keywords stored in a PDF.
- [Merge PDF Files](https://valtrinity.com/tools/pdf-merge/): Combine several PDF files into one document in the order you choose.
- [Split PDF & Extract Pages](https://valtrinity.com/tools/pdf-split/): Pull out pages, remove pages or split a PDF into smaller parts.
- [PDF Page Counter](https://valtrinity.com/tools/pdf-page-counter/): Count the pages in one or many PDF files.
- [Compress PDF](https://valtrinity.com/tools/compress-pdf/): Make a PDF smaller by shrinking its photos, with the sizes before and after.
- [Multiple Pages per Sheet](https://valtrinity.com/tools/pdf-n-up/): Print 2, 4, 6, 8 or 9 PDF pages on each sheet of paper, with a margin, gap and optional borders.
- [PDF Booklet Maker](https://valtrinity.com/tools/pdf-booklet-maker/): Reorder a PDF so that, printed double sided and folded, the pages make a booklet in the right order.
- [PDF Page Size Checker](https://valtrinity.com/tools/pdf-page-size-checker/): See the size of every page in a PDF in millimetres, inches and points, with the paper name and whether sizes are mixed.
- [Interleave PDF Pages](https://valtrinity.com/tools/interleave-pdf-pages/): Join a scan of the fronts and a scan of the backs into one PDF in the right page order.
- [Split PDF Pages in Half](https://valtrinity.com/tools/split-pdf-pages-in-half/): Cut each page of a PDF down the middle or across it, so a scanned double page spread becomes two pages.
- [Reorder & Delete PDF Pages](https://valtrinity.com/tools/reorder-pdf-pages/): Move pages up or down, remove the ones you do not want and save a new PDF.
- [JPG & PNG to PDF](https://valtrinity.com/tools/images-to-pdf/): Turn photos and images into a single PDF, one image per page.
- [PDF to JPG](https://valtrinity.com/tools/pdf-to-jpg/): Save each page of a PDF as a JPG or PNG image at 1x, 2x or 3x size.
- [PDF to Word](https://valtrinity.com/tools/pdf-to-word/): Pull the text out of a PDF and save it as an editable Word document.
- [Word to PDF](https://valtrinity.com/tools/word-to-pdf/): Turn a .docx document into a clean PDF with its headings, lists and paragraphs.
- [PDF to Text](https://valtrinity.com/tools/pdf-to-text/): Extract the text from a PDF, then copy it or download it as a .txt file.
- [HTML and Markdown to PDF](https://valtrinity.com/tools/html-to-pdf/): Turn pasted HTML or Markdown into a clean PDF with headings, lists, tables, quotes and code.
- [CSV to PDF Table](https://valtrinity.com/tools/csv-to-pdf-table/): Turn spreadsheet data or a CSV file into a neat PDF table with a header row that repeats on every page.
- [Text to PDF Converter](https://valtrinity.com/tools/text-to-pdf/): Turn pasted text into a neat, paginated PDF in A4 or Letter.
- [Quote and Estimate Generator](https://valtrinity.com/tools/quote-and-estimate-generator/): Make a professional quote or estimate as a PDF, with optional extras, a discount, a deposit, a validity date and a space to accept.
- [Purchase Order Generator](https://valtrinity.com/tools/purchase-order-generator/): Create a purchase order PDF with supplier, delivery address and date, item codes, VAT and a line for approval.
- [Credit Note Generator](https://valtrinity.com/tools/credit-note-generator/): Make a credit note PDF that cancels or reduces an invoice, with the original invoice number, the reason and VAT reversed correctly.
- [Meeting Agenda and Minutes Maker](https://valtrinity.com/tools/meeting-agenda-maker/): Plan a timed agenda that adds up to the meeting length, then print it with room for notes, or add minutes and actions afterwards.
- [UK Invoice Generator](https://valtrinity.com/tools/invoice-generator/): Fill in your details and line items and download a tidy PDF invoice with VAT worked out.

## Image Tools

- [Image Tools](https://valtrinity.com/image-tools/): Resize, crop, rotate and convert images, make favicons, add watermarks and switch pictures between web formats.
- [HEIC to JPG](https://valtrinity.com/tools/heic-to-jpg/): Turn iPhone HEIC photos into JPG files, with a quality slider.
- [WebP to PNG](https://valtrinity.com/tools/webp-to-png/): Convert WebP images to PNG files, up to 20 at a time.
- [SVG to PNG](https://valtrinity.com/tools/svg-to-png/): Convert SVG vector files to PNG at any width, with a white or transparent background.
- [AVIF to PNG](https://valtrinity.com/tools/avif-to-png/): Convert AVIF images to PNG files, up to 20 at a time.
- [Image to AVIF Converter](https://valtrinity.com/tools/image-to-avif/): Convert PNG, JPG, WebP and GIF pictures to small AVIF files.
- [Base64 Image Viewer](https://valtrinity.com/tools/base64-image-viewer/): Paste Base64 or a data address and see the picture, its type and its size.
- [PNG to JPG](https://valtrinity.com/tools/png-to-jpg/): Convert PNG images to JPG files, with a quality slider and a fill for transparent areas.
- [JPG to PNG](https://valtrinity.com/tools/jpg-to-png/): Convert JPG photos to PNG files, up to 20 at a time.
- [HEIC to PNG](https://valtrinity.com/tools/heic-to-png/): Convert iPhone HEIC photos to PNG files, up to 20 at a time.
- [WebP to JPG](https://valtrinity.com/tools/webp-to-jpg/): Convert WebP images to JPG files, with a quality slider and a fill for transparent areas.
- [Image Format Converter](https://valtrinity.com/tools/image-format-converter/): Convert up to 10 images between PNG, JPG and WebP at once.
- [Image to Base64](https://valtrinity.com/tools/image-to-base64/): Turn an image into a Base64 data URI or raw Base64 text, with size overhead.
- [Image Compressor](https://valtrinity.com/tools/image-compressor/): Shrink and resize PNG, JPEG and WebP images.
- [Background Remover](https://valtrinity.com/tools/background-remover/): Remove a plain background by colour, with a tolerance and edge softening, and save a PNG.
- [Blur Image](https://valtrinity.com/tools/blur-image/): Blur a whole picture or only the parts you drag over, such as a face, a number plate or a name.
- [Pixelate Image](https://valtrinity.com/tools/pixelate-image/): Turn parts of a picture into large blocks to hide faces, screens and personal details, or pixelate the whole thing.
- [Add Border to Image](https://valtrinity.com/tools/add-border-to-image/): Add a coloured border, padding or a square canvas around a picture.
- [Circle Crop Image](https://valtrinity.com/tools/circle-crop-image/): Crop a picture into a circle for a profile photo, with zoom, position and an optional ring.
- [Change Image Opacity](https://valtrinity.com/tools/change-image-opacity/): Make a picture partly see-through by lowering its opacity, ready to lay over something else.
- [Image Colour Replacer](https://valtrinity.com/tools/image-colour-replacer/): Swap one colour in a picture for another, or make it see-through, with control over how close a match must be.
- [Image Resizer](https://valtrinity.com/tools/image-resizer/): Resize a picture to exact pixels or a percentage, with social media presets.
- [Image Cropper](https://valtrinity.com/tools/image-cropper/): Crop a picture with a draggable box, fixed ratios and a round avatar option.
- [Rotate & Flip Image](https://valtrinity.com/tools/image-rotate-flip/): Turn a picture in 90 degree steps or any angle, and flip it either way.
- [Image Filters](https://valtrinity.com/tools/image-filters/): Apply greyscale, sepia, blur, brightness, contrast, saturation and invert with live preview.
- [Placeholder Image Generator](https://valtrinity.com/tools/placeholder-image-generator/): Make a placeholder image of any size, colour and label, as PNG, JPG, WebP or SVG.
- [Text to Image](https://valtrinity.com/tools/text-to-image/): Make a picture from a written description, in square, landscape or portrait.
- [GIF Maker](https://valtrinity.com/tools/gif-maker/): Turn several pictures into an animated GIF, with the delay between frames and the size.
- [Add Text to Image](https://valtrinity.com/tools/add-text-to-image/): Write a caption, title or message on a picture, choose the font and colour, then drag it into place.
- [Meme Generator](https://valtrinity.com/tools/meme-generator/): Add the classic top and bottom caption to any picture, with text that shrinks to fit.
- [Combine Images](https://valtrinity.com/tools/combine-images/): Join several pictures side by side or one above the other into a single picture.
- [Image Collage Maker](https://valtrinity.com/tools/image-collage-maker/): Arrange several pictures in a grid, a feature layout or a strip on a canvas size made for social media.
- [Split Image into Grid](https://valtrinity.com/tools/split-image-into-grid/): Cut a picture into equal tiles, such as a 3 by 3 grid for a social media profile, and download them all.
- [Sprite Sheet Cutter](https://valtrinity.com/tools/sprite-sheet-cutter/): Cut a sprite sheet or tile set into separate images by cell size or by number of columns and rows.
- [Image to ASCII Art](https://valtrinity.com/tools/image-to-ascii-art/): Turn a picture into text art made of letters and symbols, then copy it or save it as text or a picture.
- [Favicon Generator](https://valtrinity.com/tools/favicon-generator/): Make favicon PNGs, an .ico file and the HTML link tags from one image.
- [Add Watermark to Image](https://valtrinity.com/tools/add-watermark/): Stamp text or a logo on a picture, with position, opacity, size and tiling.
- [Image to Text Converter](https://valtrinity.com/tools/image-to-text/): Convert an image to text: read the English words in a photo or screenshot and copy them.
- [Colour Blindness Simulator](https://valtrinity.com/tools/colour-blindness-simulator/): See how colours and pictures look with protanopia, deuteranopia, tritanopia and no colour vision.
- [Image Translator](https://valtrinity.com/tools/image-translator/): Read the text in a picture, correct it if needed and translate it into another language.
- [Image Colour Palette Extractor](https://valtrinity.com/tools/image-colour-palette-extractor/): Find the main colours in a picture, with the hex code, RGB values and share of each.
- [EXIF Viewer and Remover](https://valtrinity.com/tools/exif-viewer/): See the camera, settings, date and location stored in a photo, then save a copy with that information removed.
- [Image Dimensions Checker](https://valtrinity.com/tools/image-dimensions-checker/): Check the pixel size, shape, megapixels, print size and file size of any pictures, and test them against a minimum size.
- [Image Compare Slider](https://valtrinity.com/tools/image-compare-slider/): Compare two pictures with a draggable divider, such as before and after an edit or a compressed copy.
- [Image Histogram Viewer](https://valtrinity.com/tools/image-histogram-viewer/): See the brightness and colour spread of a picture as a histogram, with averages and the share of pure black and white.
- [Colour Picker from Image](https://valtrinity.com/tools/colour-picker-from-image/): Click any pixel to get HEX, RGB and HSL, and pull a 6 colour palette from the picture.

## Generators

- [Generators](https://valtrinity.com/generators/): Pick random names, roll dice, flip coins, create passphrases, usernames, barcodes and more.
- [Random Number Generator](https://valtrinity.com/tools/random-number-generator/): Pick random whole numbers from any range, with options for no repeats and sorting.
- [Random Name Picker](https://valtrinity.com/tools/random-name-picker/): Paste a list of names, spin the wheel and pick one or more winners.
- [Dice Roller](https://valtrinity.com/tools/dice-roller/): Roll d4, d6, d20, d100 and more, add a modifier and keep a history of your rolls.
- [Coin Flip](https://valtrinity.com/tools/coin-flip/): Flip a coin once or hundreds of times, with running totals of heads and tails.
- [Passphrase Generator](https://valtrinity.com/tools/passphrase-generator/): Make a memorable passphrase from common words, with an estimate of its strength in bits.
- [Username Generator](https://valtrinity.com/tools/username-generator/): Generate usernames from adjectives and nouns, with optional numbers and themes.
- [Decision Wheel](https://valtrinity.com/tools/decision-wheel/): Type up to 20 options, spin the wheel and let it choose one.
- [Test Data Generator](https://valtrinity.com/tools/test-data-generator/): Make fake people with names, addresses, emails, phone numbers and dates, as JSON or CSV.
- [Random Generator](https://valtrinity.com/tools/random-generator/): Pick random letters, words, colours, dates or countries, with the options each one needs.
- [Random Team Generator](https://valtrinity.com/tools/random-team-generator/): Split a list of names into fair random teams, by number of teams or people in each.
- [Lottery Number Generator](https://valtrinity.com/tools/lottery-number-generator/): Random lines for Lotto, EuroMillions, Thunderball and Set For Life that follow each game's rules.
- [PIN Generator](https://valtrinity.com/tools/pin-generator/): Random PINs of 3 to 12 digits that skip patterns like 1234, 0000 and 2580.
- [Rock Paper Scissors](https://valtrinity.com/tools/rock-paper-scissors/): Play rock paper scissors against the computer, or the lizard and Spock version, with a running score.
- [Random Playing Card Generator](https://valtrinity.com/tools/random-playing-card-generator/): Draw random cards from a 52 card deck, with or without jokers, or deal hands to several players.
- [Secret Santa Generator](https://valtrinity.com/tools/secret-santa-generator/): Draw Secret Santa matches with no one buying for themselves, and reveal each match one person at a time.
- [Raffle Ticket Generator](https://valtrinity.com/tools/raffle-ticket-generator/): Print numbered raffle tickets with tear-off stubs, then draw the winning numbers.
- [Card Shuffler and Dealer](https://valtrinity.com/tools/card-shuffler-and-dealer/): Shuffle a standard pack, with jokers if you wish, and deal hands to any number of players.
- [Business Name Generator](https://valtrinity.com/tools/business-name-generator/): Get business name ideas from a keyword, in modern, classic, playful, corporate or short styles.
- [Character Name Generator](https://valtrinity.com/tools/character-name-generator/): Invent names for fantasy, sci-fi, medieval, pirate and wizard characters, each built the way that style is.
- [Writing Prompt Generator](https://valtrinity.com/tools/writing-prompt-generator/): Get a story prompt with a character, a place, a problem and a twist, or an opening line, a what if or a line of dialogue.
- [Bingo Card Generator](https://valtrinity.com/tools/bingo-card-generator/): Print 75 ball bingo cards or 90 ball strips of six tickets, and call the numbers on screen.
- [Word Search Maker](https://valtrinity.com/tools/word-search-maker/): Turn your own list of words into a printable word search puzzle with an answer key.
- [Sudoku Generator and Solver](https://valtrinity.com/tools/sudoku-generator/): Make a new sudoku with exactly one answer at four levels, play it on screen or print it, or solve one you already have.
- [Maze Generator](https://valtrinity.com/tools/maze-generator/): Make a printable maze of any size with one route from start to finish, and show the solution.
- [Graph Paper Generator](https://valtrinity.com/tools/graph-paper-generator/): Make printable graph, dot grid or lined paper to the exact spacing you choose, on A4, A3, A5 or Letter.
- [Board Game Score Sheet](https://valtrinity.com/tools/board-game-score-sheet/): Keep score for any board or card game with any number of players and rounds, with totals, places and a print option.
- [Flashcard Maker](https://valtrinity.com/tools/flashcard-maker/): Type or paste your cards, study them on the page, and save or load the set as a file.
- [Multiple Choice Quiz Maker](https://valtrinity.com/tools/multiple-choice-quiz-maker/): Write questions in plain text, play the quiz on the page, or print it with an answer key.
- [Word Ladder Puzzle Maker](https://valtrinity.com/tools/word-ladder-puzzle-maker/): Find the shortest word ladder between two words, make a printable puzzle, or check your own.
- [Handwriting Practice Sheet Generator](https://valtrinity.com/tools/handwriting-practice-sheet-generator/): Print handwriting sheets with your own words or letters to trace, copy or write on guide lines.
- [Signature Generator](https://valtrinity.com/tools/signature-generator/): Draw your signature with a mouse or finger, or type it in a handwriting style, and save a PNG with a clear background.
- [SWOT Analysis Maker](https://valtrinity.com/tools/swot-analysis-maker/): Fill in strengths, weaknesses, opportunities and threats and download a printable SWOT grid as a PDF.
- [Business Model Canvas Maker](https://valtrinity.com/tools/business-model-canvas/): Fill in the nine blocks of a business model canvas and download it as a printable one page PDF.
- [Gantt Chart Maker](https://valtrinity.com/tools/gantt-chart-maker/): Plan a project as a Gantt chart with start dates, durations and tasks that follow others, then download the chart as an image.
- [Kanban Board](https://valtrinity.com/tools/kanban-board/): Run your work on a kanban board with columns, cards, colours, due dates and limits, then export or import it as a file.
- [Eisenhower Matrix](https://valtrinity.com/tools/eisenhower-matrix/): Sort your tasks into do now, schedule, delegate and drop, with deadlines that make a task urgent automatically.
- [Weekly Rota and Shift Planner](https://valtrinity.com/tools/rota-and-shift-planner/): Plan a weekly staff rota with shift times, hours, labour cost and warnings for breaks, rest between shifts and long weeks.
- [Team Holiday Planner](https://valtrinity.com/tools/team-holiday-planner/): Track who is off and when, count working days taken and left for each person, and spot days when too many people are away.
- [Payment Chaser Letter Generator](https://valtrinity.com/tools/payment-chaser-letter-generator/): Write a polite reminder, a firm follow-up or a final notice for an overdue invoice, with late payment interest worked out.
- [Barcode Generator](https://valtrinity.com/tools/barcode-generator/): Create Code 128, EAN-13 and UPC-A barcodes with the check digit added, as SVG or PNG.
- [Wi-Fi QR Code Generator](https://valtrinity.com/tools/wifi-qr-code/): Make a QR code for your Wi-Fi network so guests can join by scanning it.
- [vCard QR Code Generator](https://valtrinity.com/tools/vcard-qr-code/): Turn contact details into a QR code that adds the person to a phone’s contacts.
- [Typing Speed Test](https://valtrinity.com/tools/typing-speed-test/): Measure your typing speed and accuracy with a short passage.
- [CPS Click Test](https://valtrinity.com/tools/cps-click-test/): Count how many times you can click in 5, 10 or 30 seconds.
- [Reaction Time Test](https://valtrinity.com/tools/reaction-time-test/): Click as soon as the box turns green and see your average time.
- [Keyboard Tester](https://valtrinity.com/tools/keyboard-tester/): See each key you press, lit up on a keyboard layout.
- [Screen Resolution Checker](https://valtrinity.com/tools/screen-resolution-checker/): See your screen size, window size, pixel ratio and orientation.
- [Dead Pixel Test](https://valtrinity.com/tools/dead-pixel-test/): Cycle through full screen solid colours to spot dead or stuck pixels.

## SEO and Website Tools

- [SEO and Website Tools](https://valtrinity.com/seo-and-website-tools/): Audit a page for SEO, find broken links, check sitemaps, test structured data, measure page weight, detect the technology a site uses and more.
- [Meta Tag & Open Graph Checker](https://valtrinity.com/tools/meta-tag-checker/): Preview a page's title, description and social link card, and spot missing tags.
- [Website Health Report](https://valtrinity.com/tools/website-health-report/): One report on whether a site loads, is set up safely and is easy to find.
- [Accessibility Checker](https://valtrinity.com/tools/accessibility-checker/): Find common accessibility problems in a web page, with a fix for each.
- [AI Crawler Checker](https://valtrinity.com/tools/ai-crawler-checker/): See which AI and search crawlers your robots.txt allows or blocks.
- [Page Speed Analyser](https://valtrinity.com/tools/page-speed-analyser/): Measure server response time, page weight and caching, with a grade and fixes.
- [Website Technology Detector](https://valtrinity.com/tools/website-technology-detector/): Find out what a website is built with, and see the evidence for each finding.
- [Page Image Audit](https://valtrinity.com/tools/page-image-audit/): Check a page's images for size, format, alt text and loading, with savings estimates.
- [SEO Checker](https://valtrinity.com/tools/seo-checker/): Audit one page for the things that affect how it shows up in search.
- [Broken Link Checker](https://valtrinity.com/tools/broken-link-checker/): Find dead, redirected and slow links on a page.
- [Sitemap & Robots.txt Checker](https://valtrinity.com/tools/sitemap-robots-checker/): Check the files that tell search engines what to crawl.
- [Structured Data Validator](https://valtrinity.com/tools/structured-data-validator/): Check a page's structured data for errors and missing properties.
- [Website Health Report by Email](https://valtrinity.com/tools/website-health-report-email/): Get a short health report for your site in your inbox every week.
- [Robots.txt Tester](https://valtrinity.com/tools/robots-txt-tester/): Test whether pasted robots.txt rules allow or block paths for a crawler.
- [HTML Heading Structure Checker](https://valtrinity.com/tools/html-heading-structure-checker/): Paste a page's HTML to see its H1 to H6 outline, the words under each heading and any skipped or missing levels.
- [Image Alt Text Checker](https://valtrinity.com/tools/image-alt-text-checker/): Paste HTML to list every image and flag missing, empty, generic, file-name or over-long alt text.
- [Internal Link Anchor Text Analyser](https://valtrinity.com/tools/internal-link-anchor-text-analyser/): Paste HTML to see the anchor text of your internal links, which words repeat and which links say nothing.
- [Canonical and Meta Robots Checker](https://valtrinity.com/tools/canonical-and-meta-robots-checker/): Paste the head of a page to check its canonical link and robots tags for errors and mixed signals.
- [External Link Rel Checker](https://valtrinity.com/tools/external-link-rel-checker/): Paste HTML to audit outbound links for nofollow, sponsored, ugc and new-tab settings.
- [Redirect Chain and Loop Finder](https://valtrinity.com/tools/redirect-chain-and-loop-finder/): Paste a list of old and new addresses to find chains, loops, clashes and self-redirects, with a cleaned list.
- [URL Structure Auditor](https://valtrinity.com/tools/url-structure-auditor/): Check a list of page addresses for length, capitals, underscores, parameters, depth and other tidiness issues.
- [Schema Markup Generator](https://valtrinity.com/tools/schema-markup-generator/): Create structured data for search engines, ready to paste into your page.
- [Redirect Rules Generator](https://valtrinity.com/tools/redirect-rules-generator/): Make redirect rules for Apache and nginx from a list of old and new addresses.
- [Meta Tag Generator](https://valtrinity.com/tools/meta-tag-generator/): Create the head tags for a web page, with length guides and a search preview.
- [Sitemap XML Generator](https://valtrinity.com/tools/sitemap-xml-generator/): Turn a list of page addresses into a ready-to-upload sitemap file.
- [Hreflang Tag Generator](https://valtrinity.com/tools/hreflang-tag-generator/): Make the language and region link tags for your pages, plus sitemap lines.
- [Robots.txt Generator](https://valtrinity.com/tools/robots-txt-generator/): Build a robots.txt file for your site, with presets for common setups.
- [Title Tag Preview](https://valtrinity.com/tools/title-tag-preview/): Preview how your page title and description may look in search results.
- [Sitemap URL Extractor](https://valtrinity.com/tools/sitemap-url-extractor/): Pull the list of addresses out of a pasted sitemap, with last modified dates.
- [Open Graph Preview](https://valtrinity.com/tools/open-graph-preview/): Type or fetch a title, description and image and see large, small and side bar link cards.
- [Search Snippet Pixel Width Checker](https://valtrinity.com/tools/serp-snippet-pixel-width-checker/): Measure the real pixel width of a title and description and see exactly where they would be cut on desktop and phone.
- [Headline Analyser](https://valtrinity.com/tools/headline-analyser/): Score a headline for length, power words, numbers and format.
- [Keyword Grouper](https://valtrinity.com/tools/keyword-grouper/): Group a long keyword list into topics by the words the phrases share, with optional search volumes.
- [Keyword Combiner](https://valtrinity.com/tools/keyword-combiner/): Combine up to four lists of words into every phrase, with optional phrase and exact match formats.
- [Content Brief Outline Builder](https://valtrinity.com/tools/content-brief-outline-builder/): Turn a main keyword and related terms into title ideas, a section outline, questions to answer and a word target.
- [Search Intent Classifier](https://valtrinity.com/tools/search-intent-classifier/): Sort a list of keywords by what the searcher wants: to learn, compare, buy or find a site.
- [Keyword Cannibalisation Checker](https://valtrinity.com/tools/keyword-cannibalisation-checker/): Find keywords that more than one of your pages is aiming at, from a list of page and keyword pairs.
- [Email Signature Generator](https://valtrinity.com/tools/email-signature-generator/): Build a simple email signature with your contact details and social links.
- [Campaign Link Builder](https://valtrinity.com/tools/utm-link-builder/): Add campaign tags to a web address, one at a time or in a list.
- [Email Subject Line Tester](https://valtrinity.com/tools/email-subject-line-tester/): Score an email subject line and see what to fix before you send it.
- [UTM Link Parser](https://valtrinity.com/tools/utm-parser/): Read the UTM source, medium and campaign from any link, and spot missing tags.
- [Social Post Character Checker](https://valtrinity.com/tools/social-post-character-checker/): Count a post against the length limits of the main kinds of social network, with web address and emoji rules.
- [Social Image Size Cropper](https://valtrinity.com/tools/social-image-size-cropper/): Crop a picture to the usual social image sizes with a zoom and a focus point, then download it.
- [Hashtag Organiser](https://valtrinity.com/tools/hashtag-organiser/): Remove repeated hashtags, turn phrases into readable tags, sort them and cap the number for a post.
- [A/B Test Significance Calculator](https://valtrinity.com/tools/ab-test-significance-calculator/): Test whether the difference between two conversion rates is real, with the p-value, z-score and confidence interval.
- [A/B Test Sample Size Calculator](https://valtrinity.com/tools/ab-test-sample-size-calculator/): Work out how many visitors each version needs before you can trust a test, and how long that takes.
- [Conversion Rate Calculator](https://valtrinity.com/tools/conversion-rate-calculator/): Turn funnel counts into step rates, drop-offs and an overall conversion rate with a margin of error.
- [CPC, CPM and CPA Calculator](https://valtrinity.com/tools/cpc-cpm-cpa-calculator/): Work out click, thousand-view and acquisition costs, plus click-through and conversion rates, from your ad numbers.
- [Customer Lifetime Value Calculator](https://valtrinity.com/tools/customer-lifetime-value-calculator/): Estimate what a customer is worth over time, compare it with the cost of winning them and see the payback period.
- [ROAS Calculator](https://valtrinity.com/tools/roas-calculator/): Work out return on ad spend, the break-even ROAS for your margin, your profit and the ROAS needed for a profit target.
- [Email List Growth Calculator](https://valtrinity.com/tools/email-list-growth-calculator/): Project the size of your email list month by month with new sign-ups, referrals and unsubscribes.
- [Engagement Rate Calculator](https://valtrinity.com/tools/engagement-rate-calculator/): Work out social engagement rate by followers, reach and impressions, and the average per post.

## Web and Security Tools

- [Web and Security Tools](https://valtrinity.com/web-security-tools/): Generate strong passwords, trace redirects, grade security headers, check SSL certificates, look up DNS records and domain registrations, check email records and website status.
- [Password Generator](https://valtrinity.com/tools/password-generator/): Create strong random passwords of any length.
- [Password Strength Checker](https://valtrinity.com/tools/password-strength-checker/): Estimate how long a password would take to guess, with pattern checks and suggestions.
- [Text Encryption Tool](https://valtrinity.com/tools/text-encryption-tool/): Lock a message with a passphrase using AES-256, and unlock it again later.
- [TOTP Code Generator and Tester](https://valtrinity.com/tools/totp-code-generator-and-tester/): Generate the six digit codes your two-step sign-in expects, and test a code against a secret key.
- [Password Policy Tester](https://valtrinity.com/tools/password-policy-tester/): Test a password against rules you choose, such as length, character types and well-known passwords.
- [Random Key Generator](https://valtrinity.com/tools/random-key-generator/): Generate random keys and secrets in hex, Base64 or letters and numbers for API keys, tokens and signing.
- [Hash Identifier](https://valtrinity.com/tools/hash-identifier/): Paste a hash to see which hash types it could be, judged from its length and format.
- [PKCE Code Challenge Generator](https://valtrinity.com/tools/pkce-code-challenge-generator/): Make a PKCE code verifier and its S256 code challenge for OAuth sign-in, plus state and nonce values.
- [SSH Key Fingerprint Calculator](https://valtrinity.com/tools/ssh-key-fingerprint-calculator/): Paste a public key to get its SHA-256 and MD5 fingerprints, type and size.
- [Security Headers Checker](https://valtrinity.com/tools/security-headers/): Grade a site's HTTP security headers from A to F.
- [CSP Header Builder](https://valtrinity.com/tools/csp-header-builder/): Build a Content-Security-Policy header by choosing where each kind of content may come from.
- [CSP Evaluator](https://valtrinity.com/tools/csp-evaluator/): Paste a Content-Security-Policy and see which parts are weak, with a grade and plain explanations.
- [SRI Hash Generator](https://valtrinity.com/tools/sri-hash-generator/): Get the integrity value for a script or style sheet and the tag that uses it.
- [Permissions-Policy Builder](https://valtrinity.com/tools/permissions-policy-builder/): Decide which browser features your pages and embedded frames may use, and get the header.
- [CORS Header Builder and Explainer](https://valtrinity.com/tools/cors-header-builder/): Build the CORS headers for your API and check whether a request will need a preflight first.
- [security.txt Generator](https://valtrinity.com/tools/security-txt-generator/): Write a security.txt file so researchers know how to report a problem on your site.
- [Set-Cookie Header Builder and Checker](https://valtrinity.com/tools/set-cookie-header-builder/): Build a Set-Cookie header with the right flags, or paste one to check it for mistakes.
- [Security Headers Generator](https://valtrinity.com/tools/security-headers-generator/): Choose HSTS and other protective headers and get the exact lines to add, with warnings about risky settings.
- [Redirect Checker](https://valtrinity.com/tools/redirect-checker/): Trace every redirect hop and status code for any URL.
- [SSL Certificate Checker](https://valtrinity.com/tools/ssl-checker/): Check a site's HTTPS certificate, issuer and expiry date.
- [DNS Lookup](https://valtrinity.com/tools/dns-lookup/): Look up A, AAAA, MX, TXT, NS, CNAME, SOA and CAA records.
- [What Is My IP](https://valtrinity.com/tools/my-ip/): See your public IP address and reverse DNS instantly.
- [WHOIS Domain Lookup](https://valtrinity.com/tools/whois-lookup/): See who registered a domain, when it expires and its name servers.
- [Website Status Checker](https://valtrinity.com/tools/website-status/): Find out whether a website is up, how fast it answers and where it redirects.
- [Domain Availability Checker](https://valtrinity.com/tools/domain-availability-checker/): See which endings are taken for a name, and when the taken ones expire.
- [IP Blacklist Checker](https://valtrinity.com/tools/ip-blacklist-checker/): Check an IP address or domain against email and abuse blocklists.
- [Subdomain Finder](https://valtrinity.com/tools/subdomain-finder/): Find a domain's subdomains and see which are live and where they point.
- [IP & ASN Lookup](https://valtrinity.com/tools/ip-asn-lookup/): See which network owns an IP address, with its ASN, range and reverse DNS.
- [SSL & Domain Expiry Alerts](https://valtrinity.com/tools/ssl-and-domain-expiry-alerts/): Save your domains and get an email before the SSL certificate or the domain registration runs out.
- [Certificate Decoder](https://valtrinity.com/tools/certificate-decoder/): Paste a PEM certificate to see who it is for, who issued it, when it expires and which names it covers.
- [CSR Decoder](https://valtrinity.com/tools/csr-decoder/): Paste a certificate signing request to check the names, key and signature before you send it to an authority.
- [SPF, DKIM & DMARC Checker](https://valtrinity.com/tools/email-dns-checker/): Check the email records that help your messages reach the inbox.
- [Email Address Validator](https://valtrinity.com/tools/email-validator/): Check an email address is written correctly and its domain accepts mail.
- [Link Unshortener](https://valtrinity.com/tools/link-unshortener/): See where a short or tracked link really goes before you click it.
- [Email Header Analyser](https://valtrinity.com/tools/email-header-analyser/): Paste the raw headers of an email to see the route, the delays and the sender checks.
- [Phishing Link Inspector](https://valtrinity.com/tools/phishing-link-inspector/): Check how a link is written for look-alike letters, hidden destinations and other tricks used in scams.
- [DMARC Record Generator](https://valtrinity.com/tools/dmarc-record-generator/): Build a DMARC record for your domain with the right policy, report addresses and alignment.
- [SPF Record Builder and Checker](https://valtrinity.com/tools/spf-record-builder/): Build an SPF record or paste one to check it, with a count of DNS look-ups against the limit of 10.
- [Cookie Scanner](https://valtrinity.com/tools/cookie-scanner/): List the cookies a page sets, with attributes, categories and weak settings flagged.
- [UK GDPR 72 Hour Breach Deadline Calculator](https://valtrinity.com/tools/uk-gdpr-breach-72-hour-deadline-calculator/): Work out the deadline to tell the ICO about a personal data breach, with a countdown and a plan.
- [URL Parameter Stripper](https://valtrinity.com/tools/url-parameter-stripper/): Remove tracking parts such as utm_ and fbclid from links before you share them.

## Guides

- [UK take-home pay explained: tax, NI, loans and pensions](https://valtrinity.com/guides/uk-take-home-pay-guide/): See how income tax, National Insurance, student loans and pension contributions reduce your salary, with worked 2026/27 examples at £25k, £40k, £60k and £100k.
- [Stamp duty in England: rates, relief and surcharges](https://valtrinity.com/guides/stamp-duty-guide/): A clear guide to Stamp Duty Land Tax in England: current bands, first-time buyer relief, the extra property surcharge and worked examples, checked October 2026.
- [How to check if your website is blocking AI crawlers](https://valtrinity.com/guides/how-to-check-if-your-website-is-blocking-ai-crawlers/): Check your robots.txt for GPTBot, ClaudeBot, PerplexityBot and Google-Extended, see what blocking really does, and allow or block each bot on purpose.
- [How to do a quick SEO audit on a small website](https://valtrinity.com/guides/how-to-do-a-quick-seo-audit/): Run a quick SEO audit on a small website with this practical checklist covering crawling, indexing, titles, links, redirects, sitemaps and structured data.
- [SPF, DKIM and DMARC explained, step by step](https://valtrinity.com/guides/spf-dkim-dmarc-explained/): A step-by-step guide to SPF, DKIM and DMARC email authentication, with example DNS records, a careful rollout order and fixes for the most common mistakes.
- [How to find and fix broken links on your website](https://valtrinity.com/guides/how-to-find-and-fix-broken-links/): Why broken links hurt visitors and search visibility, how to find them with link checkers and Search Console, and how to fix them with redirects and updates.
- [How to Merge PDF Files: Methods, Pitfalls and Tips](https://valtrinity.com/guides/how-to-merge-pdf-files/): Merge PDF files in the right order, keep file sizes manageable, number your pages correctly and avoid the common traps with scanned or protected documents.
- [How to Compress Images for the Web: Formats and Quality](https://valtrinity.com/guides/how-to-compress-images-for-the-web/): Compare image formats, choose sensible quality settings, resize before you compress and understand when WebP beats JPEG or PNG for faster, sharper pages.
- [JSON Explained for Beginners: Syntax, Errors and Formats](https://valtrinity.com/guides/json-explained-for-beginners/): JSON explained for beginners: learn the syntax rules, fix the most common errors, format data neatly and compare JSON with CSV and YAML in plain language.
- [Regex Cheat Sheet: Practical Patterns for Everyday Tasks](https://valtrinity.com/guides/regex-cheat-sheet/): A practical regex cheat sheet with checked patterns for emails, dates, UK postcodes and URLs, plus caveats so you know where each pattern falls short.
- [Cron Expressions Explained: Fields, Examples and Pitfalls](https://valtrinity.com/guides/cron-expressions-explained/): Cron expressions explained with field breakdowns, worked schedules, common mistakes such as day-of-week confusion and how time zones affect when jobs run.
- [Unix Timestamps Explained: Seconds, Milliseconds and 2038](https://valtrinity.com/guides/unix-timestamps-explained/): Unix timestamps explained: what they count, how to tell seconds from milliseconds, converting dates both ways and why the 2038 problem matters for software.
- [How to convert HEIC to JPG, step by step](https://valtrinity.com/guides/how-to-convert-heic-to-jpg/): Turn HEIC photos into JPG files that open everywhere, with sensible quality settings, batch tips and a check to make sure nothing important was lost.
- [How to convert a PDF to JPG, page by page](https://valtrinity.com/guides/how-to-convert-pdf-to-jpg/): Turn each page of a PDF into a JPG image, choose the right scale for screens or print, export a page range and check the results before you share them.
- [How to extract text from an image, and get it right](https://valtrinity.com/guides/how-to-extract-text-from-an-image/): Pull readable text out of a photo or scan with OCR. Learn how to prepare the image, get clean results from printed text and check the output for errors.
- [How to convert WebP, AVIF and SVG to PNG](https://valtrinity.com/guides/how-to-convert-webp-avif-and-svg-to-png/): Convert WebP, AVIF and SVG images to PNG when a program will not open them, with tips on transparency, width and checking the result.
- [How to make a Wi-Fi QR code for guests](https://valtrinity.com/guides/how-to-make-a-wifi-qr-code/): Create a Wi-Fi QR code so guests can join by scanning it. Covers the name and password format, escaping special characters and where to display it.
- [How to check when an SSL certificate expires](https://valtrinity.com/guides/how-to-check-when-an-ssl-certificate-expires/): Find your SSL certificate expiry date, understand how long certificates last, avoid browser warnings and set alerts so renewal never catches you out.
- [How to check DNS records after moving hosting](https://valtrinity.com/guides/how-to-check-dns-records-after-moving-hosting/): Check A, AAAA, CNAME, MX, TXT and NS records after a hosting move, understand how long changes take to spread and avoid breaking your email in the process.
- [How to split a PDF into separate files](https://valtrinity.com/guides/how-to-split-a-pdf/): Split a PDF into separate files by page range, extract the pages you need and name the results clearly, with a worked example and checks.
- [Security headers explained: what each one does](https://valtrinity.com/guides/security-headers-explained/): Learn what six useful HTTP security headers do, including HSTS, Content-Security-Policy, X-Frame-Options, Referrer-Policy and Permissions-Policy.
- [How to check your sitemap and robots.txt](https://valtrinity.com/guides/how-to-check-your-sitemap-and-robots-txt/): Check that your sitemap and robots.txt files exist, point to each other and do not block pages you want found, with a worked example and common mistakes.
- [A monthly website health checklist](https://valtrinity.com/guides/website-health-checklist/): A monthly website health checklist covering uptime, SSL and domain expiry, broken links, redirects, page weight, headers and email records.
- [How to check if an email address is valid](https://valtrinity.com/guides/how-to-check-if-an-email-address-is-valid/): Check an address for correct syntax, a domain that accepts mail, disposable providers and common typos, and why a test message is the only sure proof.
- [Redirect chains explained: 301, 302, 307 and 308](https://valtrinity.com/guides/redirect-chains-explained/): Understand 301, 302, 307 and 308 redirects, why redirect chains slow pages down, how loops happen and how to set one canonical HTTPS and www address.
- [What happens when a domain expires](https://valtrinity.com/guides/what-happens-when-a-domain-expires/): What happens when a domain expires, why grace and redemption periods vary by registry, how costs rise and how reminders and auto renewal protect you.
- [SRT vs VTT: which subtitle format to use](https://valtrinity.com/guides/srt-vs-vtt-subtitle-formats/): Compare SRT and VTT subtitle files, including timestamp formats, styling and positioning, which players accept each one and when to choose SRT or VTT.
- [How to transcribe a meeting recording](https://valtrinity.com/guides/how-to-transcribe-a-meeting-recording/): Record a meeting with permission, prepare the audio, upload it to the Video Transcriber, add speaker labels and turn the transcript into clean minutes.
- [How to add subtitles to a video](https://valtrinity.com/guides/how-to-add-subtitles-to-a-video/): Add subtitles by exporting SRT or VTT, choosing sidecar or burned-in captions, uploading alongside the video and checking the timing.
- [How to transcribe an interview](https://valtrinity.com/guides/how-to-transcribe-an-interview/): Prepare an interview recording, use speaker labels, improve accuracy, handle quotes and consent, and check the transcript before publishing.
- [Audio and video formats for transcription](https://valtrinity.com/guides/audio-and-video-formats-for-transcription/): Which audio and video formats suit transcription, from MP3 and M4A to WAV, FLAC, MP4, MOV and WebM, plus mono, bit rates and file size.
- [Student loan repayments explained: plans and monthly amounts](https://valtrinity.com/guides/student-loan-repayments-explained/): How student loan repayments work for 2026/27: plan thresholds, the 9% and 6% rates, interest, which plan you have and worked monthly examples.
- [Statutory redundancy pay explained, with a worked example](https://valtrinity.com/guides/statutory-redundancy-pay-explained/): How statutory redundancy pay works for 2026/27: eligibility, age-based weeks, the £751 weekly cap, a worked example and the six-month deadline.
- [Holiday pay and entitlement explained](https://valtrinity.com/guides/holiday-pay-and-entitlement-explained/): How UK holiday entitlement works for 2026/27: 5.6 weeks, the 28-day cap, part-year and irregular hours, and averaged pay for variable earnings.
- [Capital gains tax explained, with worked examples](https://valtrinity.com/guides/capital-gains-tax-explained/): How capital gains tax works for 2026/27: the £3,000 annual exempt amount, the 18% and 24% rates, how gains stack on income and two worked examples.
- [Dividend tax explained, with a worked example](https://valtrinity.com/guides/dividend-tax-explained/): How dividend tax works in 2026/27: the £500 allowance, the 10.75%, 35.75% and 39.35% rates, how dividends stack on wages and a worked example.
- [UK income tax bands explained: rates for 2026/27](https://valtrinity.com/guides/uk-income-tax-bands-explained/): The UK income tax bands for 2026/27: the £12,570 personal allowance, 20%, 40% and 45% rates, how the allowance tapers above £100,000 and examples.
- [How to check text for AI signals, and why no detector is reliable](https://valtrinity.com/guides/how-to-check-text-for-ai-signals/): What AI content detectors can and cannot tell you, how to look for signs of machine-written text, and why a score must never be used to accuse anyone.
- [How to cite a website in APA, MLA and Harvard](https://valtrinity.com/guides/how-to-cite-a-website/): How to cite a web page in APA 7, MLA 9 and Harvard, with the same example in each style, what to do when details are missing and how to check your work.
- [How to summarise a long document](https://valtrinity.com/guides/how-to-summarise-a-long-document/): A practical method to summarise a long report, article or chapter: skim the structure, pull out key points, write it up and check it against the source.
- [How to convert cm to inches and back, with a table](https://valtrinity.com/guides/how-to-convert-cm-to-inches/): Convert centimetres to inches and back with one exact number, a quick table and worked examples for height, screens and furniture.
- [Metric vs imperial: which units the UK still uses](https://valtrinity.com/guides/metric-vs-imperial-uk-units/): A plain guide to where the UK still uses miles, pints, stones and inches, where it uses metric, and the exact conversions to move between the two.
- [How to calculate percentage change, with worked examples](https://valtrinity.com/guides/how-to-calculate-percentage-change/): Work out percentage increase, decrease and reverse percentages with one formula, plus the traps with percentage points, successive changes and base values.
- [Standard deviation explained with a worked example](https://valtrinity.com/guides/standard-deviation-explained/): Learn what standard deviation measures, how to calculate it for a population and a sample step by step, and how to read the result.
- [Mean, median and mode explained with examples](https://valtrinity.com/guides/mean-median-mode-explained/): Understand the three averages, how to find each one by hand, why salary figures often mislead, and which average to use for different kinds of data.
- [Converting between fractions, decimals and percentages](https://valtrinity.com/guides/convert-fractions-decimals-percentages/): Convert between fractions, decimals and percentages with simple rules, a table of common values and worked examples for prices, recipes and test marks.
- [Hex, binary and decimal: how number bases work](https://valtrinity.com/guides/hex-binary-decimal-number-bases/): How binary, octal, decimal and hexadecimal work, how to convert between them by hand with worked examples, and where each base shows up in real life.
- [Ohm's law explained with worked examples](https://valtrinity.com/guides/ohms-law-explained/): Ohm's law links voltage, current and resistance. Learn the formulas, power, series and parallel circuits, with UK mains examples.
- [How to work out your BMR and daily calories](https://valtrinity.com/guides/how-to-work-out-bmr-and-daily-calories/): Work out your basal metabolic rate with the Mifflin-St Jeor formula, scale it by activity for daily calories, and use it for weight goals.
- [BMI explained: how to calculate it and what it means](https://valtrinity.com/guides/bmi-explained-uk/): How BMI is calculated in kilograms and metres, the NHS ranges, a worked example in stones and pounds, and the limits of BMI for muscle, age and ethnicity.
- [How to work out your due date, step by step](https://valtrinity.com/guides/how-to-work-out-your-due-date/): Work out a pregnancy due date from your last period or conception date, adjust for cycle length, and plan key dates for work.
- [How many working days are in 2027 in the UK?](https://valtrinity.com/guides/working-days-in-2027-uk/): There are 253 working days in 2027 in England and Wales, 252 in Scotland and 251 in Northern Ireland. See every bank holiday and a monthly count.
- [How to calculate the days between two dates](https://valtrinity.com/guides/how-to-calculate-days-between-two-dates/): Count the days, weeks and months between two dates by hand, avoid the inclusive versus exclusive trap, and handle leap years, deadlines and week numbers.
- [GMT, BST and UTC: UK time and time zones explained](https://valtrinity.com/guides/gmt-bst-and-time-zones-explained/): When UK clocks change in 2026 and 2027, how GMT, BST and UTC differ, and how to convert meeting times to New York, Europe, India, Tokyo and Sydney.
- [Leap years explained: the rules, the dates and the edge cases](https://valtrinity.com/guides/leap-years-explained/): Why we have leap years, the three-part rule that decides them, the next leap years to 2048, and what 29 February means for birthdays, pay and contracts.
- [How to calculate timesheet hours and pay correctly](https://valtrinity.com/guides/how-to-calculate-timesheet-hours-and-pay/): Add up hours and minutes on a timesheet, convert to decimals, deduct breaks, apply overtime and check pay against the 2026 UK minimum wage rates.
- [Speed, distance and time: formulas and worked examples](https://valtrinity.com/guides/speed-distance-time-formulas-explained/): Use the speed distance time triangle to find any of the three, convert mph, km/h and m/s, work out average speed correctly, and plan journeys and runs.
- [MPG, litres per 100 km and fuel cost per mile explained](https://valtrinity.com/guides/mpg-and-fuel-cost-per-mile-explained/): Work out your real mpg from a tank, convert mpg to litres per 100 km, and calculate fuel cost per mile and for a journey, with worked UK examples.
- [How to calculate how much paint you need for a room](https://valtrinity.com/guides/how-to-calculate-how-much-paint-you-need/): Measure walls and ceilings, subtract doors and windows, allow for coats and waste, and turn the area into litres and tin sizes with a full worked example.
- [Pythagoras' theorem explained with real-life uses](https://valtrinity.com/guides/pythagoras-theorem-explained/): Learn a squared plus b squared equals c squared, find any side of a right-angled triangle, and use it for ladders, TVs, roofs and squaring.
- [How APR works on UK loans and credit cards](https://valtrinity.com/guides/how-apr-works-uk-loans-credit-cards/): What APR includes, what representative APR means, how to compare loans and cards with worked monthly payment examples, and how APR differs from AER.
- [Compound interest explained with UK savings examples](https://valtrinity.com/guides/compound-interest-explained-uk/): How compound interest grows savings, the formula with worked examples, the rule of 72, regular deposits, and how inflation and tax affect the real result.
- [How mortgage overpayments work, with worked examples](https://valtrinity.com/guides/how-mortgage-overpayments-work/): See how paying extra on a UK repayment mortgage cuts the term and the interest, with worked monthly and lump sum examples, and the limits to check first.
- [UK VAT explained: rates, registration and calculations](https://valtrinity.com/guides/uk-vat-explained/): How VAT works in the UK, with the 20%, 5% and 0% rates, how to add and remove VAT, input and output VAT, and the £90,000 registration threshold.
- [Profit margin vs markup: the difference, with examples](https://valtrinity.com/guides/profit-margin-vs-markup-explained/): Margin and markup both describe profit but use different bases. Learn the formulas, convert between them, and set prices correctly with worked UK examples.
- [Rental yield explained: gross, net and cash return](https://valtrinity.com/guides/rental-yield-explained-uk/): How to work out gross and net rental yield on a UK buy-to-let, with a worked example covering stamp duty, costs and a mortgage.
- [How to write a meta description that gets clicks](https://valtrinity.com/guides/how-to-write-a-meta-description/): Write meta descriptions that match the page and earn clicks: the right length, what to include, before and after examples, and how to check them in bulk.
- [What is a good readability score? Flesch scores explained](https://valtrinity.com/guides/readability-scores-explained/): How the Flesch Reading Ease and grade level scores are calculated, what a good score is for different readers, and practical ways to make writing easier.
- [Reading time and speaking time: how many words a minute?](https://valtrinity.com/guides/reading-time-and-speaking-time-explained/): Average reading and speaking speeds, how to work out reading time for an article, and how many words you need for a talk, speech or video script.
- [Open Graph tags: control how your links look when shared](https://valtrinity.com/guides/open-graph-tags-and-social-share-images/): How Open Graph tags set the title, description and image shown when a link is shared, the 1200 by 630 image size, example code and how to test the result.
- [UTM parameters explained: track where your visitors come from](https://valtrinity.com/guides/utm-parameters-explained/): What the five UTM parameters mean, how to build a tagged link, naming rules that keep reports clean, with examples and mistakes to avoid.
- [Schema markup for small sites: a practical guide](https://valtrinity.com/guides/schema-markup-guide-for-small-sites/): What structured data is, which types matter for a small site, a worked JSON-LD example, and how to test it without promising rich results.
- [How to compress a PDF and keep it readable](https://valtrinity.com/guides/how-to-compress-a-pdf-and-keep-it-readable/): Why PDFs get large, what compression changes, and a step by step way to cut file size for email and uploads while keeping text sharp and scans legible.
- [How to sign a PDF without printing it](https://valtrinity.com/guides/how-to-sign-a-pdf-without-printing/): Add a typed, drawn or image signature to a PDF, learn when an electronic signature is valid in the UK, and avoid the mistakes that get forms rejected.
- [How to resize images to exact sizes and aspect ratios](https://valtrinity.com/guides/how-to-resize-images-to-exact-dimensions/): Resize and crop images to exact pixel sizes without stretching, work out aspect ratios by hand, and pick sizes for web, social, print and passport photos.
- [Colour contrast ratios and WCAG: a plain guide](https://valtrinity.com/guides/colour-contrast-and-wcag-explained/): How contrast ratios are calculated, what 4.5 to 1 and 3 to 1 mean for text and buttons, worked examples with real colours, and how to fix low contrast.
- [How long should a password be? Length, words and entropy](https://valtrinity.com/guides/how-long-should-a-password-be/): Why length beats complexity, how to work out password strength with a simple calculation, and why three random words are a good choice for UK users.
- [UK postcode, NI number and IBAN formats explained](https://valtrinity.com/guides/uk-postcodes-ni-numbers-and-ibans-explained/): How UK postcodes, National Insurance numbers, sort codes, IBANs and VAT numbers are structured, which formats are valid, and what a format check can prove.
- [HTTP status codes explained: 200, 301, 404, 500 and more](https://valtrinity.com/guides/http-status-codes-explained/): What the main HTTP status codes mean, which ones matter for visitors and search engines, and how to diagnose 4xx and 5xx errors on your own website.
- [UCAS Tariff points explained with grade tables](https://valtrinity.com/guides/ucas-tariff-points-explained/): How UCAS Tariff points work for A levels, AS levels and the EPQ, with a grade table, worked examples such as ABB and A*AB, and what to check on offers.

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