How to convert kilocalories to kilojoules
- Take the value in kilocalories.
- Use the formula kilojoules = kilocalories × 4.184.
- For example, 105 kcal is 439.32 kJ.
About kilocalories and kilojoules
A kilocalorie is exactly 4.184 kilojoules, so multiply kcal by 4.184 to get kJ. To do it in your head, multiply by 4 and add 5%: 500 kcal gives 2,100 kJ against the exact 2,092 kJ.
The kilocalorie is the “Calorie” on US food labels and in most diet apps. Labels in the EU show both kJ and kcal, and labels in Australia and New Zealand lead with kJ, so comparing products across countries means converting.
Examples
- 105 kcal (a medium banana) is 439.32 kJ
- 140 kcal (a 12 oz can of Coca-Cola) is 585.76 kJ
- 2,000 kcal (the daily reference intake on food labels) is 8,368 kJ
- 2,500 kcal (the NHS daily calorie guide for men) is 10,460 kJ
Kilocalories to kilojoules chart
| Kilocalories (kcal) | Kilojoules (kJ) |
|---|---|
| 1 | 4.18 |
| 10 | 41.84 |
| 50 | 209.2 |
| 100 | 418.4 |
| 150 | 627.6 |
| 200 | 836.8 |
| 250 | 1,046 |
| 300 | 1,255.2 |
| 400 | 1,673.6 |
| Kilocalories (kcal) | Kilojoules (kJ) |
|---|---|
| 500 | 2,092 |
| 600 | 2,510.4 |
| 750 | 3,138 |
| 1,000 | 4,184 |
| 1,500 | 6,276 |
| 1,800 | 7,531.2 |
| 2,000 | 8,368 |
| 2,500 | 10,460 |
| 3,000 | 12,552 |