Convert Kilocalorie to Kilojoule
Convert Kilocalorie to Kilojoule instantly. 1 kcal = 4.184 kJ. Formula, worked examples and a quick reference table.
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One kilocalorie equals 4.184 kilojoules. To convert any number of kilocalories to kilojoules, multiply by 4.184.
The converter above works in both directions and updates as you type. Below you will find the formula, a worked example and a reference table of common values.
Kilocalorie to Kilojoule formula
To go the other way, use kilocalorie = kilojoule ÷ 4.184.
About these units
The "calorie" on food labels is actually a kilocalorie — 1,000 small calories. One kilocalorie is 4.184 kilojoules.
Kilocalorie to Kilojoule conversion table
| Kilocalorie | Kilojoule |
|---|---|
| 1 kcal | 4.184 kJ |
| 2 kcal | 8.368 kJ |
| 3 kcal | 12.552 kJ |
| 5 kcal | 20.92 kJ |
| 10 kcal | 41.84 kJ |
| 20 kcal | 83.68 kJ |
| 25 kcal | 104.6 kJ |
| 50 kcal | 209.2 kJ |
| 100 kcal | 418.4 kJ |
| 250 kcal | 1,046 kJ |
| 500 kcal | 2,092 kJ |
| 1,000 kcal | 4,184 kJ |
Frequently asked questions
How many kilojoules are in a kilocalorie? +
There are 4.184 kilojoules in one kilocalorie.
What is 10 kcal in kJ? +
10 kcal equals 41.84 kJ. Multiply 10 by 4.184.
How do I convert kilojoule back to kilocalorie? +
Use kilocalorie = kilojoule ÷ 4.184. The converter above handles both directions, or see our dedicated Kilojoule to Kilocalorie page.