Kilocalories to Kilojoules Converter
Type a value in kilocalories to see it in kilojoules. It works both ways: type in the kilojoules box to convert back.
Formula
To convert kilocalories to kilojoules, multiply by 4.184.
1 kcal = 4.184 kJ and 1 kJ = 0.239005736138 kcal.
Kilocalories to kilojoules table
| Kilocalories | Kilojoules |
|---|---|
| 50 kcal | 209.2 kJ |
| 100 kcal | 418.4 kJ |
| 200 kcal | 836.8 kJ |
| 250 kcal | 1,046 kJ |
| 500 kcal | 2,092 kJ |
| 1,000 kcal | 4,184 kJ |
| 1,500 kcal | 6,276 kJ |
| 2,000 kcal | 8,368 kJ |
| 2,500 kcal | 10,460 kJ |
Worked examples
100 kcal in kilojoules
100 kcal
418.4 kJ
100 × 4.184 = 418.4
500 kcal in kilojoules
500 kcal
2,092 kJ
500 × 4.184 = 2,092
2,000 kcal in kilojoules
2,000 kcal
8,368 kJ
2,000 × 4.184 = 8,368
About Kilocalories to Kilojoules Converter
This converter turns kilocalories into kilojoules as you type, and works the other way too: type in the kilojoules box to convert back. To convert kilocalories to kilojoules, multiply by 4.184. For example, 100 kcal is 418.4 kJ, and 500 kcal is 2,092 kJ.
Energy appears on food labels, electricity bills and heating ratings, each in its own unit, so converting between kilojoules, kilocalories, kilowatt hours and BTU helps compare them. Both units have exact definitions, so the converter gives an exact result, rounded only for display. Use the table below for common values, or set the decimal places to round the answer for a form or a label.
How to use Kilocalories to Kilojoules Converter
- Type the amount in kilocalories in the first box.
- Read the answer in kilojoules in the second box and in the result line below.
- To convert the other way, type in the kilojoules box instead, or use the swap button to open the kilojoules to kilocalories page.
- Choose a number of decimal places if you need a rounded figure, then copy the result line.
Common uses
- Working out heating or electricity costs
- Comparing boiler, heater or air conditioner ratings
- Science and engineering homework
- Comparing food energy on labels
Frequently asked questions
How many kilojoules are in one kilocalorie?
There are 4.184 kilojoules in one kilocalorie. This figure is exact, because both units have fixed definitions.
How do I convert kilocalories to kilojoules?
To convert kilocalories to kilojoules, multiply by 4.184. For example, 2,000 kcal is 8,368 kJ.
How do I convert kilojoules to kilocalories?
Going the other way, divide by 4.184 (the same as multiplying by 0.2390057361). The kilojoules to kilocalories converter does this for you.
What is 1,000 kcal in kilojoules?
1,000 kcal is 4,184 kJ.
Are calories on food labels the same as calories in science?
No. The calories on food labels are kilocalories, each 1,000 small calories. A label showing 250 kcal means 250,000 small calories, or about 1,046 kilojoules.