The kilojoule
The kilojoule (kJ) equals exactly 1,000 joules. It is the standard unit on EU and many non-US nutrition labels — 1 dietary calorie ≈ 4.184 kJ. It also appears in industrial-process specifications and energy-storage ratings.
Kilojoules to Calories Converter
1 kJ = 239.006 cal (kilojoule → calorie)
1 kJ = 239.006 cal
1 kilojoule equals 239.006 calories. To convert kilojoules to calories, multiply the kilojoule value by 239.006. For quick reference: 1 kJ = 239.006 cal, 5 kJ = 1195.03 cal, 10 kJ = 2390.06 cal, 100 kJ = 23900.6 cal.
Formula
Calories = Kilojoules × 239.006Quick
When to use kilojoules → calories
Kilojoules to small (thermochemical) calories multiplies by 239.0057 — equivalently, kJ × 1000 ÷ 4.184. A 1 kJ energy transfer is 239 small calories. Be careful with what 'calorie' means here: this is the physics calorie of 4.184 J, not the food Calorie. A banana's 450 kJ is 107,552 small calories but only 107.6 kcal — quoting the former on a diet app would be a thousand-fold blunder. For nutrition, convert kJ to kcal instead.
Battery chemists comparing a cell's rated energy density, often given in kJ per gram, against classic thermochemical reference tables convert to small calories to align with older calorimetry literature. A 4.184 kJ energy release is exactly 1,000 calories; a denser 20 kJ/g electrode material corresponds to 4,780 cal/g. Because most modern materials-science papers report exclusively in joules or kilojoules, this conversion mainly surfaces when cross-referencing a decades-old calorimetry dataset from before the SI convention, when calories were still the default reporting unit.
How to convert kilojoules to calories
Take your value
Start with your value in kilojoules.
Multiply by 239.006
Multiply the kilojoule value by 239.006. This is the exact conversion factor from kilojoules to calories.
Read the result
The product is your value in calories. For example, 5 kJ × 239.006 = 1195.03 cal.
Conversion formula
The exact factor from kilojoules to calories is 239.006.
Calories = Kilojoules × 239.006
Kilojoules to Calories conversion table
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Kilojoules (kJ) | Calories (cal) |
|---|---|
| 0.001 kJ | 0.23901 cal |
| 0.01 kJ | 2.3901 cal |
| 0.1 kJ | 23.901 cal |
| 0.5 kJ | 119.5 cal |
| 1 kJ | 239.01 cal |
| 1.5 kJ | 358.51 cal |
| 2 kJ | 478.01 cal |
| 5 kJ | 1195 cal |
| 10 kJ | 2390.1 cal |
| 20 kJ | 4780.1 cal |
| 50 kJ | 11950 cal |
| 100 kJ | 23901 cal |
| 200 kJ | 47801 cal |
| 250 kJ | 59751 cal |
| 500 kJ | 119503 cal |
| 1000 kJ | 239006 cal |
| 2000 kJ | 478011 cal |
| 2500 kJ | 597514 cal |
| 3600 kJ | 860421 cal |
| 5000 kJ | 1195029 cal |
| 7500 kJ | 1792543 cal |
| 10000 kJ | 2390057 cal |
| 25000 kJ | 5975143 cal |
| 50000 kJ | 11950287 cal |
| 100000 kJ | 23900574 cal |
| 250000 kJ | 59751434 cal |
| 500000 kJ | 119502868 cal |
| 1000000 kJ | 239005736 cal |
| 2000000 kJ | 478011472 cal |
| 3600000 kJ | 860420650 cal |
| 5000000 kJ | 1195028681 cal |
| 10000000 kJ | 2390057361 cal |
| 25000000 kJ | 5975143403 cal |
| 50000000 kJ | 11950286807 cal |
| 100000000 kJ | 23900573614 cal |
| 250000000 kJ | 59751434034 cal |
| 500000000 kJ | 119502868069 cal |
| 1000000000 kJ | 239005736138 cal |
| 2000000000 kJ | 478011472275 cal |
| 5000000000 kJ | 1195028680688 cal |
| 10000000000 kJ | 2390057361377 cal |
| 20000000000 kJ | 4780114722753 cal |
| 50000000000 kJ | 11950286806883 cal |
| 100000000000 kJ | 23900573613767 cal |
| 1000000000000 kJ | 239005736137667 cal |
| 10000000000000 kJ | 2.3901 × 10^15 cal |
| 100000000000000 kJ | 2.3901 × 10^16 cal |
| 1000000000000000 kJ | 2.3901 × 10^17 cal |
| 10000000000000000 kJ | 2.3901 × 10^18 cal |
| 100000000000000000 kJ | 2.3901 × 10^19 cal |
Real-world reference
A medium banana provides about 450 kJ of food energy. A laptop battery typically stores 200–300 kJ. In calories, that gives you: 1 kJ = 239.006 cal, 10 kJ = 2390.06 cal, 100 kJ = 23900.6 cal.
Frequently asked questions
- How many calories are in 1 kilojoule?
- 1 kilojoule equals 239.006 calories.
- How do I convert kilojoules to calories?
- Multiply the kilojoule value by 239.006. So x kJ × 239.006 = the equivalent in cal.
- What is 5 kilojoules in calories?
- 5 kilojoules equals 1195.03 calories.
- What is 10 kilojoules in calories?
- 10 kilojoules equals 2390.06 calories.
- What is 100 kilojoules in calories?
- 100 kilojoules equals 23900.6 calories.
- How do I convert back from calories to kilojoules?
- Multiply the calorie value by 0.004184. For example, 1 cal = 0.004184 kJ.
- Is the kilojoule bigger than the calorie?
- Yes. 1 kilojoule is larger than 1 calorie — specifically 239.006 times larger.
- Are these conversion factors exact?
- The factor is derived directly from the SI definitions of kilojoule and calorie; the displayed value is rounded for readability, and the browser computes using IEEE 754 double-precision arithmetic.
About the kilojoule and the calorie
The calorie
Convertitive uses the thermochemical (small) calorie, defined as exactly 4.184 joules — the energy needed to raise 1 g of water by 1 °C. Do not confuse it with the large calorie (kcal) used on US nutrition labels, which is 1,000 of these small calories.