How Many Joules in a Calorie?
Quick Answer
There are approximately 4.184 joules in a thermochemical calorie.
1 calorie = 4.184 joules
Understanding the Conversion
One thermochemical calorie equals exactly 4.184 joules. Note that the 'Calorie' (capital C) used in food nutrition is actually a kilocalorie (kcal), equal to 1,000 small calories or 4,184 joules. The joule is the SI unit of energy, while the calorie is an older unit still used in nutrition and chemistry.
Formula
1 calorie = 4.184 joules
Common Examples
| Description | Value |
|---|---|
| 1 food Calorie (kcal) | 4,184 joules |
| A 2,000 kcal daily diet | About 8,368,000 joules (8.37 MJ) |
| Burning 500 kcal exercising | About 2,092,000 joules |
Quick Reference Table
Use this table for quick conversions between calorie and joules:
| calorie | joules |
|---|---|
| 1 | 4.184 |
| 2 | 8.368 |
| 5 | 20.92 |
| 10 | 41.84 |
| 25 | 104.6 |
| 50 | 209.2 |
| 100 | 418.4 |
Frequently Asked Questions
How Many Joules in a Calorie?
There are approximately 4.184 joules in a thermochemical calorie. One thermochemical calorie equals exactly 4.184 joules. Note that the 'Calorie' (capital C) used in food nutrition is actually a kilocalorie (kcal), equal to 1,000 small calories or 4,184 joules. The joule is the SI unit of energy, while the calorie is an older unit still used in nutrition and chemistry.
What is the formula to convert calorie to joules?
The formula is: 1 calorie = 4.184 joules. To convert, multiply the number of calories by 4.184 to get the equivalent in joules.
How do I convert joules to calorie?
To convert joules to calorie, divide the number of joules by 4.184. For example, 20.92 joules equals 5 calories.