kJ to Kcal Converter
Convert kilojoules to kilocalories — divide by 4.184. Results update as you type; exact factors shown.
One kilojoule is 0.239 kilocalorie (food Calorie) — see the exact factor, not a rounded rule of thumb.
How the kj to kcal converter works
Energy converts through the joule. A thermochemical calorie is exactly 4.184 J, so a food Calorie (kcal) is 4.184 kJ. A kilowatt-hour is exactly 3.6 MJ. A BTU is 1,055.056 J and a US therm is 100,000 BTU.
The US uses customary units (US gallon, short ton, °F) in daily life; NIST SP 811 gives the exact SI factors.
Common energy conversions
| From | To | Units |
|---|---|---|
| 100 kJ | 23.9006 kcal | kilojoules to kilocalorie (food Calorie) |
| 200 kJ | 47.8011 kcal | kilojoules to kilocalorie (food Calorie) |
| 418 kJ | 99.9044 kcal | kilojoules to kilocalorie (food Calorie) |
| 500 kJ | 119.5029 kcal | kilojoules to kilocalorie (food Calorie) |
| 1,000 kJ | 239.0057 kcal | kilojoules to kilocalorie (food Calorie) |
| 2,000 kJ | 478.0115 kcal | kilojoules to kilocalorie (food Calorie) |
| 4,184 kJ | 1,000 kcal | kilojoules to kilocalorie (food Calorie) |
| 5,000 kJ | 1,195.0287 kcal | kilojoules to kilocalorie (food Calorie) |
| 8,368 kJ | 2,000 kcal | kilojoules to kilocalorie (food Calorie) |
| 10,000 kJ | 2,390.0574 kcal | kilojoules to kilocalorie (food Calorie) |
| 12,000 kJ | 2,868.0688 kcal | kilojoules to kilocalorie (food Calorie) |
| 15,000 kJ | 3,585.086 kcal | kilojoules to kilocalorie (food Calorie) |
Units in this converter and their exact factors
| Unit | Symbol | One unit in joules |
|---|---|---|
| joule | J | 1 joule |
| kilojoule | kJ | 1,000 joule |
| megajoule | MJ | 1,000,000 joule |
| calorie (thermochemical) | cal | 4.184 joule |
| kilocalorie (food Calorie) | kcal | 4,184 joule |
| watt-hour | Wh | 3,600 joule |
| kilowatt-hour | kWh | 3,600,000 joule |
| British thermal unit | BTU | 1,055.05585262 joule |
| therm (US) | thm | 105,505,585.262 joule |
| foot-pound | ft·lb | 1.3558179483 joule |
FAQFrequently asked questions about energy conversion
How many kcal in a kJ?
0.239.
What is 8,368 kJ?
2,000 kcal — a common daily reference intake.
How do I estimate?
Divide by four and take a little off.
Which countries label in kJ?
Australia and New Zealand lead with kilojoules; the EU shows both.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Institute of Standards and Technology (NIST) — United States's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.