Convert Kilocalories to Kilojoules
kcal to kJ · energy conversion
What are kilocalories and kilojoules?
A kilocalorie (the food Calorie) is 1,000 small calories, the unit on US nutrition labels. A kilojoule is 1,000 joules, used for food energy outside the US. For reference: a food Calorie is one kilocalorie (4,184 J), and home electricity is billed in kilowatt-hours.
How to convert kilocalories to kilojoules
1 kcal = 4.184 kJ. To convert, multiply the number of kilocalories by 4.184. For example, 5 kcal = 20.92 kJ, and 20 kcal = 83.68 kJ. To go the other way, multiply kilojoules by 0.239006 (since 1 kJ = 0.239006 kcal).
Kilocalories to Kilojoules conversion table
| Kilocalories (kcal) | Kilojoules (kJ) |
|---|---|
| 1 | 4.184 |
| 10 | 41.84 |
| 100 | 418.4 |
| 500 | 2,092 |
| 1,000 | 4,184 |
| 2,000 | 8,368 |
| 5,000 | 20,920 |
FAQ
What is 1 kcal in kJ?
1 kcal = 4.184 kJ. To convert any amount, multiply the number of kilocalories by 4.184.
How do I convert kilojoules back to kilocalories?
Go the other way: 1 kJ = 0.239006 kcal, so multiply kilojoules by 0.239006 to get kilocalories.
Is a kilocalorie bigger than a kilojoule?
Yes — 1 kcal is the larger unit, equal to 4.184 kJ.
Are these energy conversions exact?
They use the standard internationally-defined conversion factors. Results are rounded to six significant figures for readability, which is accurate enough for everyday and most technical use.