How to convert kilojoules to kilocalories
To convert kilojoules to kilocalories, multiply by 0.239005736138. Energy conversions connect nutrition, electricity bills, heating systems and physics.
Kilojoule to Kilocalorie conversion table
| Kilojoule (kJ) | Kilocalorie (kcal) |
|---|---|
| 0.1 kJ | 0.0239005736138 kcal |
| 0.5 kJ | 0.119502868069 kcal |
| 1 kJ | 0.239005736138 kcal |
| 2 kJ | 0.478011472275 kcal |
| 3 kJ | 0.717017208413 kcal |
| 4 kJ | 0.956022944551 kcal |
| 5 kJ | 1.19502868069 kcal |
| 10 kJ | 2.39005736138 kcal |
| 20 kJ | 4.78011472275 kcal |
| 25 kJ | 5.97514340344 kcal |
| 50 kJ | 11.9502868069 kcal |
| 100 kJ | 23.9005736138 kcal |
| 500 kJ | 119.502868069 kcal |
| 1,000 kJ | 239.005736138 kcal |
About the units
Kilojoule (kJ)
A kilojoule is 1,000 joules and appears on food labels in many countries.
Kilocalorie (kcal)
A kilocalorie (food Calorie) equals 1,000 small calories, or 4,184 joules.
How to use this converter
- Type the number of kilojoules (kJ) in the input box.
- The result in kilocalories appears instantly — no button needed.
- See the same value in every other energy unit just below.
- Use “Swap units” to convert kilocalories back to kilojoules.
When you’ll use the kilojoule to kilocalorie conversion
Converting kilojoules to kilocalories comes up more often than you might expect — for example when sizing a heater or air conditioner, understanding your electricity bill in kWh, or comparing food energy in kcal and kJ. Type your number once and you get the exact answer plus every related unit, so you don’t need to convert twice.
💡 For a quick estimate in your head, multiply by about 0.24 (the exact factor is 0.239005736138).
Watch out for these mix-ups
- Food “Calories” are kilocalories (kcal), not small calories.
- kW is power (a rate); kWh is energy (an amount).
Tips for better results
- Double-check which system a unit belongs to (for example US vs UK gallons).
- Use the swap button to convert in the opposite direction instantly.
- Bookmark the conversions you use most — each pair has its own page.
Frequently asked questions
How many kilocalories are in one kilojoule?
One kilojoule equals 0.239005736138 kilocalories. 0.239005736138 is the exact factor used by this converter.
How do I convert kilojoules to kilocalories?
Multiply the value in kilojoules by 0.239005736138. To go the other way, multiply kilocalories by 4.184.
What is 10 kJ in kcal?
10 kJ = 2.39005736138 kcal. Also, 5 kJ = 1.19502868069 kcal and 100 kJ = 23.9005736138 kcal.
What is the difference between a kilojoule and a kilocalorie?
A kilojoule is 1,000 joules and appears on food labels in many countries. A kilocalorie (food Calorie) equals 1,000 small calories, or 4,184 joules.
Is this tool free and private?
Yes — the Kilojoule to Kilocalorie is completely free with no sign-up, and it runs entirely in your browser, so the values you enter are never uploaded to our servers.
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