Calories to Kilojoules Converter
Convert kilocalories (food Calories) to kilojoules instantly. Type a value, change either unit, or press swap to go the other way. 1 kilocalorie (food Calorie) = 4.184 kilojoules.
1 kilocalorie (food Calorie) = 4.184 kilojoules
How to convert kilocalories (food Calories) to kilojoules
kilojoules = kilocalories (food Calories) × 4.184
To convert kilocalories (food Calories) to kilojoules, multiply the value by 4.184. To go back from kilojoules to kilocalories (food Calories), divide by the same number (or multiply by 0.2390057361).
Worked examples
- 150 kcal: 150 × 4.184 = 627.6 kJ
- 200 kcal: 200 × 4.184 = 836.8 kJ
- 250 kcal: 250 × 4.184 = 1,046 kJ
Multiply kilocalories by 4.2. A 2,000-Calorie daily intake is about 8,368 kJ.
Calories to Kilojoules conversion table
Kilocalories to Kilojoules
| kcal | kJ |
|---|---|
| 50 | 209.2 |
| 100 | 418.4 |
| 150 | 627.6 |
| 200 | 836.8 |
| 250 | 1,046 |
| 500 | 2,092 |
| 1,000 | 4,184 |
| 1,500 | 6,276 |
| 2,000 | 8,368 |
| 2,500 | 10,460 |
Kilojoules to Kilocalories
| kJ | kcal |
|---|---|
| 50 | 11.950287 |
| 100 | 23.900574 |
| 150 | 35.85086 |
| 200 | 47.801147 |
| 250 | 59.751434 |
| 500 | 119.50287 |
| 1,000 | 239.00574 |
| 1,500 | 358.5086 |
| 2,000 | 478.01147 |
| 2,500 | 597.51434 |
Energy equivalents
See how one kilocalorie (food Calorie) and one kilojoule compare with every other energy unit on the site.
1 kilocalorie (food Calorie) equals
| Unit | Value |
|---|---|
| joules (J) | 4,184 |
| kilojoules (kJ) | 4.184 |
| calories (small) (cal) | 1,000 |
| watt-hours (Wh) | 1.162222 |
| kilowatt-hours (kWh) | 0.001162222 |
| British thermal units (BTU) | 3.965667 |
1 kilojoule equals
| Unit | Value |
|---|---|
| joules (J) | 1,000 |
| calories (small) (cal) | 239.0057 |
| kilocalories (food Calories) (kcal) | 0.2390057 |
| watt-hours (Wh) | 0.2777778 |
| kilowatt-hours (kWh) | 0.0002777778 |
| British thermal units (BTU) | 0.9478171 |
When you need to convert kilocalories (food Calories) to kilojoules
Nutrition labels in the US list Calories, while labels in Australia, New Zealand and much of Europe list kilojoules, often with the kilocalorie figure in brackets. Converting is useful when you compare products from different countries or follow a diet plan written in the other unit.
About the units
Kilocalorie (food Calorie) (kcal)
A kilocalorie is 1,000 small calories, or 4,184 joules. The "Calories" on food labels are actually kilocalories.
Kilojoule (kJ)
A kilojoule is 1,000 joules. It is used for food energy on labels in Australia, New Zealand and Europe, usually alongside kilocalories.
Frequently asked questions
How do I convert kilocalories (food Calories) to kilojoules?
Multiply the number of kilocalories (food Calories) by 4.184. For example, 10 kilocalories (food Calories) × 4.184 = 41.84 kilojoules.
How many kilojoules are in one kilocalorie (food Calorie)?
There are 4.184 kilojoules in one kilocalorie (food Calorie).
How many kilocalories (food Calories) are in one kilojoule?
There are 0.2390057361 kilocalories (food Calories) in one kilojoule.
Are food Calories the same as calories?
A food "Calorie" (capital C) is a kilocalorie, which is 1,000 of the small calories used in physics. This converter treats the Calories on a food label as kilocalories. You can pick the small calorie from the unit drop-down if you need it.
Can I convert other energy units with this tool?
Yes. Use the From and To drop-downs in the converter to choose any energy unit, or press the swap button to reverse the conversion. All calculations use internationally defined conversion factors.