Joules to Kilocalories Converter
1 joule ≈ 0.000239005736 kilocalories
This is the unit written as "Calories" on nutrition labels.
1 joule equals 0.000239006 kilocalories
How to convert joules to kilocalories
Calories here are thermochemical (4.184 J), while BTU uses the International Table definition. A kilowatt-hour is energy (3.6 MJ), not power; a food Calorie is a kilocalorie.
kcal = J ÷ 4184One kilocalorie corresponds to 4184 joules, so divide by that figure. Displayed constants may be rounded; the converter uses the stored factor before rounding the result.
0.00239006 kcal ≈ 10 ÷ 4184This is the unit written as "Calories" on nutrition labels.
Joules to kilocalories conversion table
Common values in joules, converted to kilocalories.
| Joules (J) | Kilocalories (kcal) |
|---|---|
| 1 | 0.00023900574 |
| 2 | 0.00047801147 |
| 3 | 0.00071701721 |
| 4 | 0.00095602294 |
| 5 | 0.0011950287 |
| 10 | 0.0023900574 |
| 20 | 0.0047801147 |
| 25 | 0.0059751434 |
| 50 | 0.011950287 |
| 100 | 0.023900574 |
| 250 | 0.059751434 |
| 500 | 0.11950287 |
| 1,000 | 0.23900574 |
About these units
jouleJ
The SI derived unit of energy: one newton acting through one metre.
kilocaloriekcal
One thousand thermochemical calories: exactly 4,184 joules.
Sources and precision
Table results are rounded to 8 significant digits; formula constants may be rounded to 10. Worked example answers use 6 significant digits. The converter starts at 6 significant digits and lets you change display precision. Calculations use the stored factors without intermediate rounding. Exact unit definitions do not make an input measurement more precise; conventional and measured factors follow the assumptions stated here.