Convert Joules to Kilocalories
One joule equals 0.000239006 kilocalories. Type any value to convert joules to kilocalories instantly — with a full reference table below.
Convert Joules to Kilocalories
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How to convert Joules to Kilocalories
To convert joules to kilocalories, multiply by 0.000239006. One joule equals 0.000239006 kcal, and one kilocalorie equals 4,184 J.
- Take the value in joules — for example 7.5 J.
- Multiply by 0.000239006 (the number of kilocalories in one joule).
- 7.5 × 0.000239006 = 0.00179254 kcal.
Joules to Kilocalories conversion table
| Joules | Kilocalories |
|---|---|
| 1 J | 0.000239006 kcal |
| 2 J | 0.000478011 kcal |
| 5 J | 0.00119503 kcal |
| 10 J | 0.00239006 kcal |
| 20 J | 0.00478011 kcal |
| 50 J | 0.0119503 kcal |
| 100 J | 0.0239006 kcal |
| 200 J | 0.0478011 kcal |
| 500 J | 0.119503 kcal |
| 1,000 J | 0.239006 kcal |
| 2,000 J | 0.478011 kcal |
| Kilocalories | Joules |
|---|---|
| 1 kcal | 4,184 J |
| 2 kcal | 8,368 J |
| 5 kcal | 20,920 J |
| 10 kcal | 41,840 J |
| 20 kcal | 83,680 J |
| 50 kcal | 209,200 J |
| 100 kcal | 418,400 J |
| 200 kcal | 836,800 J |
| 500 kcal | 2,092,000 J |
| 1,000 kcal | 4,184,000 J |
| 2,000 kcal | 8,368,000 J |
About converting Joules to Kilocalories
Joules (J) and Kilocalories (kcal) are both units of energy. The exact factor is 1 J = 0.000239006 kcal, so multiply by 0.000239006 to go from joules to kilocalories (or divide to go back).
The conversion runs entirely in your browser. Need the reverse? Use the Kilocalories to Joules converter, or the full unit converter for every unit at once.
Real-world energy in joules and kilocalories
| Example | Joules | Kilocalories |
|---|---|---|
| One food Calorie (kcal) | 4,184 J | 1 kcal |
| A 100 W bulb running for one hour | 360,000 J | 86.04207 kcal |
| A smartphone battery (≈19 Wh) | ≈ 69,300 J | ≈ 16.5631 kcal |
“≈” marks typical values; the rest are defined or measured figures.
The units
The SI unit of energy: the work done by one newton over one metre.
Used for: Science and food labels (kJ).
1,000 calories, exactly 4,184 J — the 'Calorie' on food labels.
Used for: Nutrition and diets.
The thermochemical calorie is exactly 4.184 J and a kilowatt-hour is exactly 3.6 MJ, so these factors are exact.