Protein Intake Calculator
Enter your weight and choose what you are aiming for. You get a daily range in grams, and how it looks across meals.
This is an estimate for general information and is not medical advice. Anyone with kidney disease, or advised to limit protein, should follow their care team.
Worked examples
General adult
70 kg, general health
52.5 g protein a day
70 x 0.75.
Building muscle
75 kg, resistance training
120 to 165 g protein a day
75 x 1.6 and 75 x 2.2.
About Protein Intake Calculator
How much protein you need depends on your size and what you are doing. The UK reference nutrient intake for adults is 0.75 grams of protein for each kilogram of body weight a day. People who exercise regularly, older adults and those building muscle are usually advised to eat more. This calculator multiplies your weight by the range for your aim and gives you a daily figure in grams.
The ranges come from published sources. Sports nutrition bodies describe about 1.2 to 2.0 g/kg for athletes. A 2018 analysis of resistance training trials found gains in muscle levelled off at about 1.6 g/kg, with 2.2 g/kg covering most people. For older adults an expert group suggests 1.0 to 1.2 g/kg. This is an estimate and not medical advice.
How to use Protein Intake Calculator
- Choose metric or imperial units and enter your weight.
- Pick the aim that is closest to yours.
- Read the daily range in grams and the grams per kilogram.
- Use the meal split to spread your protein across three or four meals.
Common uses
- Planning meals for strength training
- Checking whether a diet gives enough protein
- Setting a protein target for older age
- Comparing protein needs between two people of different weights
Frequently asked questions
How much protein does an adult need?
In the UK, the reference nutrient intake is 0.75 grams for every kilogram of body weight. A 70 kg adult needs about 52 grams a day. That is enough for most people who do not exercise heavily.
How much protein do I need to build muscle?
Studies suggest muscle gain from resistance training levels off at about 1.6 g/kg, with an upper estimate of 2.2 g/kg. For a 75 kg lifter that is roughly 120 to 165 grams a day. Training itself matters more than going above this range.
Do older adults need more protein?
Yes, many experts suggest 1.0 to 1.2 g/kg for adults aged 65 and over to help keep muscle. This is higher than the general adult figure. Your GP or dietitian can advise on your own needs.
Is it harmful to eat more protein?
For most healthy adults, intakes at the top of these ranges are considered acceptable. People with kidney disease or other conditions may be told to limit protein, so follow your care team’s advice. This is an estimate and not medical advice.
Should I use my current weight?
Use your current weight for most people. If you are well above or below a healthy weight, ask a dietitian whether to use a different figure. The ranges here are for adults.