UnitConCalories (kcal) to Kilojoules Converter
Convert kilocalories (food Calories) to kilojoules for nutrition label reading, dietary planning, and comparing food energy values between US and international packaging. Many countries list energy in both kcal and kJ.
Formula
Multiply kilocalories by 4.184 to get kilojoules. To reverse, divide kilojoules by 4.184 to get kilocalories.
Quick reference
| Kilocalorie (kcal) | Kilojoule (kJ) |
|---|---|
| 50 | 209.2 |
| 100 | 418.4 |
| 150 | 627.6 |
| 200 | 836.8 |
| 250 | 1,046 |
| 500 | 2,092 |
| 1000 | 4,184 |
| 1500 | 6,276 |
| 2000 | 8,368 |
| 2500 | 10,460 |
About these units
Kilocalorie
The kilocalorie became the standard unit for expressing food energy in the late 19th century following Wilbur Atwater's studies on human metabolism. US food labels continue to use Calories (kcal) as the primary energy unit.
Kilojoule
The kilojoule (1000 J) is the metric alternative to the kilocalorie for food energy. European Union, Australian, and New Zealand food regulations require kJ on nutrition labels alongside kcal.