Convert Joules to Calories
J to cal · energy conversion
What are joules and calories?
The joule is the SI unit of energy, the work done by one newton acting over one meter. A small calorie is the energy to heat one gram of water by 1 °C, about 4.184 J. For reference: a food Calorie is one kilocalorie (4,184 J), and home electricity is billed in kilowatt-hours.
How to convert joules to calories
1 J = 0.239006 cal. To convert, multiply the number of joules by 0.239006. For example, 5 J = 1.19503 cal, and 20 J = 4.78011 cal. To go the other way, multiply calories by 4.184 (since 1 cal = 4.184 J).
Joules to Calories conversion table
| Joules (J) | Calories (cal) |
|---|---|
| 1 | 0.239006 |
| 10 | 2.39006 |
| 100 | 23.9006 |
| 500 | 119.503 |
| 1,000 | 239.006 |
| 2,000 | 478.011 |
| 5,000 | 1,195.03 |
FAQ
What is 1 J in cal?
1 J = 0.239006 cal. To convert any amount, multiply the number of joules by 0.239006.
How do I convert calories back to joules?
Go the other way: 1 cal = 4.184 J, so multiply calories by 4.184 to get joules.
Is a joule bigger than a calorie?
No — 1 J is the smaller unit, equal to 0.239006 cal (it takes 4.184 J to make one cal).
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.