Convert kJ to kcal
To convert kJ to kcal, divide the value in kJ by 4.184 — the same as multiplying by about 0.239006. It turns the kilojoules on Australian, New Zealand and EU food labels into the calories most diet apps count. This kj to kcal converter works both ways: type kJ or kcal into either box above and the other box, the worked formula and the chart below update as you type.
The kilojoule (kJ) is 1,000 joules. The joule, named after the physicist James Prescott Joule, is the SI unit of energy. Australia and New Zealand label food energy in kilojoules, and EU labels show kJ next to kcal. One kilojoule is 0.239006 kilocalories.
The kilocalorie (kcal) is the energy needed to warm one kilogram of water by about 1 °C. The “Calorie” with a capital C on food labels is the same thing as a kilocalorie. Going the other way, one kilocalorie equals 4.184 kilojoules. Nutrition labels in the US, UK and India show kcal, and most diet and fitness apps count calories in kcal.
How to convert kj to kcal with this tool
- Type a number into the Kilojoules (kJ) box — it starts at 8,700 kJ as an example.
- Read the answer in the Kilocalories (kcal) box and in the result panel, which also shows the formula with your number.
- To go the other way, type into the kcal box, or press the swap button to open the kcal to kJ converter with your value carried over.
- Choose how many decimal places you want, or tap a quick value such as 100 kJ, 500 kJ, 1,000 kJ.
- Press Copy result to paste the conversion into a message, spreadsheet or note.
kJ to kcal converter features
Converts both ways
Type in the kJ box to get kcal, or in the kcal box to get kJ. The other box follows instantly.
Exact factor
Calculations use 1 kcal = 4.184 kJ, and rounding is applied only to the answer you see — choose Auto or 0–10 decimal places.
Formula with your number
The working is shown under the result, for example 8,700 kJ ÷ 4.184 = 2,079.35 kcal, so you can check it or copy the method.
Quick values and chart
Tap common values like 100 kJ, 500 kJ, 1,000 kJ, or read the kJ-to-kcal table further down this page.
kJ to kcal formula
The formula is kcal = kJ ÷ 4.184. It is exact because the thermochemical kilocalorie used for food energy is defined as exactly 4.184 kJ.
The reverse formula is kJ = kcal × 4.184 — or use the kcal to kJ converter. Three worked examples:
- The 8,700 kJ average adult daily intake used on Australian labels: 8,700 kJ ÷ 4.184 = 2,079.35 kcal
- A 1,000 kJ meal: 1,000 kJ ÷ 4.184 = 239.01 kcal
- A 400 kJ serving: 400 kJ ÷ 4.184 = 95.6 kcal
kJ to kcal quick reference
The values people look up most often, worked out with the exact factor:
- 1 kJ = 0.239006 kcal
- 1 kcal = 4.184 kJ
- 100 kJ = 23.9 kcal
- 500 kJ = 119.5 kcal
- 1,000 kJ = 239.01 kcal
- 2,000 kJ = 478.01 kcal
Quick tip: Divide by 4 and subtract about 5%: 2,000 kJ → 500 − 25 = 475 kcal, close to the exact 478.01 kcal.
Related conversions: the full energy converter.
kJ to kcal conversion table
Values in kcal are rounded to 2 decimal places (more for very small numbers). For any value not listed, type it into the converter above.
| kJ | kcal | kJ | kcal |
|---|---|---|---|
| 1 | 0.239 | 900 | 215.11 |
| 10 | 2.39 | 1,000 | 239.01 |
| 50 | 11.95 | 1,500 | 358.51 |
| 100 | 23.9 | 2,000 | 478.01 |
| 200 | 47.8 | 2,500 | 597.51 |
| 250 | 59.75 | 3,000 | 717.02 |
| 300 | 71.7 | 4,000 | 956.02 |
| 400 | 95.6 | 5,000 | 1,195.03 |
| 500 | 119.5 | 6,000 | 1,434.03 |
| 600 | 143.4 | 7,000 | 1,673.04 |
| 700 | 167.3 | 8,000 | 1,912.05 |
| 750 | 179.25 | 8,700 | 2,079.35 |
| 800 | 191.2 | 10,000 | 2,390.06 |
kJ to kcal FAQ
How many kilocalories is 500 kJ?
500 kilojoules is 119.5 kilocalories: 500 kJ ÷ 4.184 = 119.5 kcal.
How do I convert kj to kcal?
Divide the value in kJ by 4.184 — the same as multiplying by about 0.239006. For example, 2,000 kJ ÷ 4.184 = 478.01 kcal. To convert back, multiply the value in kcal by 4.184 — or use the kcal to kJ converter.
How many kilojoules are in one kilocalorie?
One kilocalorie is 4.18 kilojoules, because 1 kcal × 4.184 = 4.18 kJ.
What is 2,000 kJ in kcal?
Why do some sources use 4.1868 instead of 4.184?
There are two calories: the thermochemical calorie (4.184 J), used for food labelling, and the International Table calorie (4.1868 J) found in some engineering tables. The difference is under 0.1%; this page uses 4.184, so 1,000 kJ = 239.01 kcal.