Kilocalories (food Calories) to Kilojoules
Type a value in Kilocalories (food Calories) and get the result in Kilojoules, calculated exactly.
100 Kilocalories (food Calories) = 418.4 Kilojoules
Precision
Exact factorThis result is exact.
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Formula
kJ = kcal × 4.184
To convert Kilocalories (food Calories) to Kilojoules, multiply the value by 4.184.
Worked examples
- 1 kcal × 4.184 = 4.184 kJ
- 100 kcal × 4.184 = 418.4 kJ
- 50 kcal × 4.184 = 209.2 kJ
This factor is exact by definition.
Conversion table
| Kilocalories (food Calories) (kcal) | Kilojoules (kJ) |
|---|---|
| 1 | 4.184 |
| 2 | 8.368 |
| 3 | 12.552 |
| 4 | 16.736 |
| 5 | 20.92 |
| 6 | 25.104 |
| 7 | 29.288 |
| 8 | 33.472 |
| 9 | 37.656 |
| 10 | 41.84 |
| 15 | 62.76 |
| 20 | 83.68 |
| 25 | 104.6 |
| 30 | 125.52 |
| 40 | 167.36 |
| 50 | 209.2 |
| 60 | 251.04 |
| 70 | 292.88 |
| 75 | 313.8 |
| 80 | 334.72 |
| 90 | 376.56 |
| 100 | 418.4 |
Values marked ≈ are rounded; the rest are exact.
Reverse table: Kilojoules to Kilocalories (food Calories)
| Kilojoules (kJ) | Kilocalories (food Calories) (kcal) |
|---|---|
| 1 | ≈ 0.2390057 |
| 2 | ≈ 0.4780115 |
| 3 | ≈ 0.7170172 |
| 4 | ≈ 0.9560229 |
| 5 | ≈ 1.195029 |
| 6 | ≈ 1.434034 |
| 7 | ≈ 1.67304 |
| 8 | ≈ 1.912046 |
| 9 | ≈ 2.151052 |
| 10 | ≈ 2.390057 |
| 15 | ≈ 3.585086 |
| 20 | ≈ 4.780115 |
| 25 | ≈ 5.975143 |
| 30 | ≈ 7.170172 |
| 40 | ≈ 9.560229 |
| 50 | ≈ 11.95029 |
| 60 | ≈ 14.34034 |
| 70 | ≈ 16.7304 |
| 75 | ≈ 17.92543 |
| 80 | ≈ 19.12046 |
| 90 | ≈ 21.51052 |
| 100 | ≈ 23.90057 |
Unit definitions
- Kilocalories (food Calories) kcal
- Exactly 4184 joules; the "Calorie" on food labels.
- Kilojoules kJ
- Exactly 1000 joules.
Questions people ask
Kilocalories (food Calories) to Kilojoules: what is the conversion factor?
One kcal is 4.184 kJ.
How do I convert Kilocalories (food Calories) to Kilojoules?
Use the formula above. For example, 100 kcal = 418.4 kJ.
Is the conversion exact?
Yes. Both units have exact definitions, so the factor is exact; a result is only rounded when its decimals never end.
Factors checked 19 October 2026.