How to convert joules to kilocalories
kcal = J × 0.0002390057361Because one kilocalorie equals 4,184 joules, you can also divide: kcal = J ÷ 4,184.
A joule is smaller than a kilocalorie: it takes 4,184 joules to make one kilocalorie.
Worked examples
- 1 joule1 J × 0.0002390057361 = 0.0002390057361 kcal
- 5 joules5 J × 0.0002390057361 = 0.001195028681 kcal
- 10 joules10 J × 0.0002390057361 = 0.002390057361 kcal
- 20 joules20 J × 0.0002390057361 = 0.004780114723 kcal
- 100 joules100 J × 0.0002390057361 = 0.02390057361 kcal
Joules to kilocalories conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Joules (J) | Kilocalories (kcal) |
|---|---|
| 0.1 J | 0.000023900574 kcal |
| 0.25 J | 0.000059751434 kcal |
| 0.5 J | 0.00011950287 kcal |
| 1 J | 0.00023900574 kcal |
| 2 J | 0.00047801147 kcal |
| 3 J | 0.00071701721 kcal |
| 4 J | 0.00095602294 kcal |
| 5 J | 0.0011950287 kcal |
| 6 J | 0.0014340344 kcal |
| 7 J | 0.0016730402 kcal |
| 8 J | 0.0019120459 kcal |
| 9 J | 0.0021510516 kcal |
| 10 J | 0.0023900574 kcal |
| Joules (J) | Kilocalories (kcal) |
|---|---|
| 12 J | 0.0028680688 kcal |
| 15 J | 0.003585086 kcal |
| 20 J | 0.0047801147 kcal |
| 25 J | 0.0059751434 kcal |
| 30 J | 0.0071701721 kcal |
| 40 J | 0.0095602294 kcal |
| 50 J | 0.011950287 kcal |
| 75 J | 0.01792543 kcal |
| 100 J | 0.023900574 kcal |
| 250 J | 0.059751434 kcal |
| 500 J | 0.11950287 kcal |
| 1,000 J | 0.23900574 kcal |
About the units
Joule (J)
The SI unit of energy: the work done by a force of one newton over one metre, or one watt for one second. Lifting an apple by one metre takes about 1 J.
Kilocalorie (kcal)
One thousand small calories, or 4,184 J. The “Calories” on nutrition labels are kilocalories.
Frequently asked questions
How many kilocalories are in one joule?
There are 0.0002390057361 kilocalories in one joule, and this value is exact by definition.
How do I convert joules to kilocalories?
Multiply the number of joules by 0.0002390057361. For example, 10 J × 0.0002390057361 = 0.002390057361 kcal.
How many joules are in one kilocalorie?
One kilocalorie equals 4,184 joules. That is the reverse factor, 1 ÷ 0.0002390057361.
What is 10 joules in kilocalories?
10 J = 0.002390057361 kcal.
Is this J to kcal converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.