kJ to calories Converter Online – Easily convert Kilojoules (kJ) to Calories (kcal) and vice versa with our free mobile-friendly tool. Learn the formulas, definitions, and see examples of energy conversion.
Understanding Kilojoules and Calories
Whether you are reading food labels or tracking your fitness goals, understanding the difference between Kilojoules (kJ) and Calories (kcal) is essential. While both measure energy, they are used in different parts of the world.
What is a Calorie (kcal)?
The “Calorie” found on food nutrition labels is technically a kilocalorie (kcal). It is the amount of heat energy required to raise the temperature of one kilogram of water by one degree Celsius. This is the standard unit of measurement in the United States and broadly used in everyday conversation.
What is a Kilojoule (kJ)?
The Kilojoule is the unit of energy in the International System of Units (SI). It is the standard measurement used in Australia, New Zealand, and the UK. It is a more precise measurement of energy than the Calorie.
The Conversion Formula
To convert between these two units manually, you can use the following standard conversion factors:
To convert Calories to Kilojoules:
Multiply Calories by 4.184
Formula: kcal × 4.184 = kJ
To convert Kilojoules to Calories:
Divide Kilojoules by 4.184 (or multiply by 0.239)
Formula: kJ / 4.184 = kcal
Examples
- Example 1: An apple has 52 Calories. How many Kilojoules is that?
52 × 4.184 = 217.5 kJ - Example 2: A snack bar contains 800 kJ. How many Calories is that?
800 ÷ 4.184 = 191 Calories
Quick Conversion Table
| Calories (kcal) | Kilojoules (kJ) |
|---|---|
| 1 kcal | 4.18 kJ |
| 50 kcal | 209 kJ |
| 100 kcal | 418 kJ |
| 200 kcal | 837 kJ |
| 500 kcal | 2092 kJ |
| 2000 kcal (Daily Avg) | 8368 kJ |