Convert Kilojoules to Calories
One kilojoule equals 239.0057 calories. Type any value to convert kilojoules to calories instantly — with a full reference table below.
Convert Kilojoules to Calories
Converted in your browser — nothing you enter is sent anywhere.
How to convert Kilojoules to Calories
To convert kilojoules to calories, multiply by 239.0057. One kilojoule equals 239.0057 cal, and one calorie equals 0.004184 kJ.
- Take the value in kilojoules — for example 7.5 kJ.
- Multiply by 239.0057 (the number of calories in one kilojoule).
- 7.5 × 239.0057 = 1,792.543 cal.
Quick mental estimate: Multiply the number of kilojoules by 239 (accurate to better than 0.05%).
Kilojoules to Calories conversion table
| Kilojoules | Calories |
|---|---|
| 1 kJ | 239.0057 cal |
| 2 kJ | 478.0115 cal |
| 5 kJ | 1,195.029 cal |
| 10 kJ | 2,390.057 cal |
| 20 kJ | 4,780.115 cal |
| 50 kJ | 11,950.29 cal |
| 100 kJ | 23,900.57 cal |
| 200 kJ | 47,801.15 cal |
| 500 kJ | 119,502.9 cal |
| 1,000 kJ | 239,005.7 cal |
| 2,000 kJ | 478,011.5 cal |
| Calories | Kilojoules |
|---|---|
| 1 cal | 0.004184 kJ |
| 2 cal | 0.008368 kJ |
| 5 cal | 0.02092 kJ |
| 10 cal | 0.04184 kJ |
| 20 cal | 0.08368 kJ |
| 50 cal | 0.2092 kJ |
| 100 cal | 0.4184 kJ |
| 200 cal | 0.8368 kJ |
| 500 cal | 2.092 kJ |
| 1,000 cal | 4.184 kJ |
| 2,000 cal | 8.368 kJ |
About converting Kilojoules to Calories
Kilojoules (kJ) and Calories (cal) are both units of energy. The exact factor is 1 kJ = 239.0057 cal, so multiply by 239.0057 to go from kilojoules to calories (or divide to go back).
The conversion runs entirely in your browser. Need the reverse? Use the Calories to Kilojoules converter, or the full unit converter for every unit at once.
Real-world energy in kilojoules and calories
| Example | Kilojoules | Calories |
|---|---|---|
| One food Calorie (kcal) | 4.184 kJ | 1,000 cal |
| A 100 W bulb running for one hour | 360 kJ | 86,042.07 cal |
| A smartphone battery (≈19 Wh) | ≈ 69.3 kJ | ≈ 16,563.1 cal |
| One kilowatt-hour | 3,600 kJ | 860,420.7 cal |
“≈” marks typical values; the rest are defined or measured figures.
The units
1,000 joules.
Used for: Food energy on labels in Australia and the EU.
The thermochemical calorie: exactly 4.184 J — energy to warm 1 g of water by about 1 °C.
Used for: Chemistry. Food 'Calories' are kilocalories.
The thermochemical calorie is exactly 4.184 J and a kilowatt-hour is exactly 3.6 MJ, so these factors are exact.