Convert Calories to Kilojoules
1 cal = 0.004184 kJ
Conversion Table
| calories (cal) | kilojoules (kJ) |
|---|---|
| 0.5 | 0.002092 |
| 1 | 0.004184 |
| 2 | 0.008368 |
| 5 | 0.02092 |
| 10 | 0.04184 |
| 25 | 0.1046 |
| 50 | 0.2092 |
| 100 | 0.4184 |
| 250 | 1.046 |
| 500 | 2.092 |
| 1000 | 4.184 |
How to Convert calories to kilojoules
To convert calories to kilojoules, multiply the value by the conversion factor:
For example: 10 cal = 0.04184 kJ
About calories and kilojoules
The Conversion Formula
To convert calories to kilojoules, multiply the value by the conversion factor: 1 cal = 0.004184 kJ. For a worked example, suppose you need to convert 25 cal to kilojoules: 25 × 0.004184 = 0.1046 kJ. To convert in the opposite direction, divide by 0.004184, or equivalently multiply by 239.01.
About calories
The calorie (lowercase c) was originally defined as the heat required to raise 1 gram of water by 1°C. It is a tiny unit, often called the 'gram calorie'. It is mostly used in chemistry and physics today, not for food. calories are commonly used in Chemistry experiments, Thermodynamics, Specific heat capacity, and Physics problems.
Heating 1 gram of water by 1°C takes 1 calorie.
About kilojoules
The kilojoule (kJ) is the standard unit for food energy in most of the world (Australia, Europe, etc.), replacing the Calorie. One food Calorie (kcal) is approximately 4.2 kJ. It provides a more precise measure of energy intake than the large Calorie. kilojoules are commonly used in Food labels (Global), Exercise machines, Diet planning, and Thermodynamics, Metabolic rate tracking.
A slice of bread has about 300-400 kJ.
When Would You Convert calories to kilojoules?
Converting between calories and kilojoules is one of the most common energy conversions. You might need this conversion when working with international specifications, following instructions written for a different measurement system, or comparing values across different standards. Having the conversion factor (1 cal = 0.004184 kJ) memorized or bookmarked can save time in professional and everyday contexts alike.