Convert Kilojoules to Kilocalories
Kilojoules to kilocalories is the conversion you need when a nutrition label gives energy in kJ but you count in Calories — the two numbers printed side by side on food packaging worldwide. One kilojoule is approximately 0.2390057361376673 kilocalories, so the kilocalorie figure always comes out much smaller.
Kilojoules to Kilocalories conversion table
| Kilojoules (kJ) | Kilocalories (kcal) |
|---|---|
| 1 | 0.239006 |
| 2 | 0.478011 |
| 3 | 0.717017 |
| 5 | 1.195029 |
| 10 | 2.390057 |
| 20 | 4.780115 |
| 50 | 11.950287 |
| 100 | 23.900574 |
| 500 | 119.502868 |
| 1,000 | 239.005736 |
The formula
To convert kilojoules to kilocalories, multiply the number of kilojoules by 0.2390057361376673:
kilocalories = kilojoules × 0.2390057361376673
A worked example
Say a snack lists 2000 kJ and you want it in food Calories:
2000 × 0.2390057361376673 = 478.01147 kcal
So a 2000 kJ snack is about 478 food Calories.
Why it's an approximation
The factor 0.2390057361376673 is a rounded value. A kilocalorie is built from the thermochemical calorie, which is defined as exactly 4.184 joules — so 1000 joules is one calorie divided by 4.184, which doesn't land on a clean number. That's why the kilojoules-to-kilocalories factor rounds to roughly 0.239. Worth knowing: the "Calorie" on a nutrition label (capital C) is a kilocalorie, so this is the same math your food packaging uses to print kJ and kcal next to each other.
When you'll use it
Reading a nutrition label that gives energy in kilojoules when you think in Calories, comparing two foods where one is labeled in kJ and the other in kcal, or checking a recipe's energy figure against a daily Calorie target.
Frequently asked questions
Is a kilocalorie the same as a food Calorie?
Yes. The 'Calorie' with a capital C on a nutrition label is a kilocalorie (kcal) — one food Calorie equals one kilocalorie. So a 478 kcal snack is a 478-Calorie snack.
How many kilocalories are in a kilojoule?
About 0.2390057361376673 kilocalories. It's a rounded figure — roughly 0.239 — because a kilocalorie is defined from the calorie, and the calorie and joule don't divide evenly.
Is the kilojoules to kilocalories conversion exact?
No. The factor is approximately 0.2390057361376673, rounded for everyday use. It comes from the thermochemical calorie, which is exactly 4.184 joules, so the reverse direction is tidy but this one stays approximate.