kJ to Calories Converter
Convert kilojoules (kJ) to kilocalories (food Calories) (kcal) instantly. Type a value — the result updates as you type, and the swap button converts the other way.
kJ to Calories formula
kcal = kJ ÷ 4.184
1 kilojoule = 0.239 kilocalories (food Calories) · 1 kilocalorie (food Calorie) = 4.18 kilojoules
To convert kilojoules to kilocalories (food Calories), divide the value by 4.184. For example, 500 kJ:
kcal = 500 ÷ 4.184kcal = 119.502868
So 500 kJ = 119.5 kcal.
Mental math shortcut
Quick mental estimate: multiply by 0.24 (divide by about 4.2). For 500 kJ that gives about 120 kcal — within 1% of the exact answer. Use the exact formula when precision matters.
kJ to Calories conversion table
Calories back to kJ
The same values converted the other way, rounded for everyday use:
| Kilocalories (food Calories) | Kilojoules |
|---|---|
| 23.9 kcal | 100 kJ |
| 47.8 kcal | 200 kJ |
| 100 kcal | 418.4 kJ |
| 119.5 kcal | 499.99 kJ |
| 239.01 kcal | 1000.02 kJ |
| 478.01 kcal | 1999.99 kJ |
| 1000 kcal | 4184 kJ |
| 2079.35 kcal | 8700 kJ |
About the units
Kilojoules (kJ)
A kilojoule is 1,000 joules. Food labels in Australia, the EU and elsewhere show energy in kJ.
Kilocalories (food Calories) (kcal)
A kilocalorie is 1,000 small calories, written “Calorie” on food labels. 1 kcal = 4.184 kJ.
Frequently asked questions
How many kilocalories (food Calories) are in a kilojoule?
One kilojoule equals 0.239 kilocalories (food Calories).
What is 500 kJ in Calories?
500 kJ = 119.5 kcal.
How do I convert Calories back to kJ?
Multiply the kilocalories (food Calories) by 4.184. Or use the Calories to kJ converter.