Calories to Joules Converter
How to convert calories to joules
joules = calories × 4.184
To convert calories to joules, multiply the number of calories by 4.184.
1 cal = 4.184 J
Examples
- One kilocalorie, or one food Calorie: 1,000 cal × 4.184 = 4,184 J
- 500 cal × 4.184 = 2,092 J
Good to know
This uses the thermochemical calorie, exactly 4.184 joules. For food energy you probably want kilocalories, which are 1000 times larger.
This is the thermochemical calorie, exactly 4.184 J. It is the small calorie: the "Calories" on food labels are kilocalories, 1000 times larger. The International Table calorie (4.1868 J) is slightly different.
Calories to joules conversion table
| Calories (cal) | Joules (J) |
|---|---|
| 1 cal | 4.184 J |
| 2 cal | 8.368 J |
| 5 cal | 20.92 J |
| 10 cal | 41.84 J |
| 20 cal | 83.68 J |
| 50 cal | 209.2 J |
| 100 cal | 418.4 J |
| 200 cal | 836.8 J |
| 250 cal | 1,046 J |
| 500 cal | 2,092 J |
| 1,000 cal | 4,184 J |
| 2,000 cal | 8,368 J |
| 2,500 cal | 10,460 J |
| 5,000 cal | 20,920 J |
| 10,000 cal | 41,840 J |
Unit definitions
- Calorie (cal)
- The thermochemical calorie is defined as exactly 4.184 joules, roughly the energy needed to heat one gram of water by one degree Celsius.
- Joule (J)
- The joule is the SI unit of energy, equal to the work done by a force of one newton over one meter, or one watt for one second.