Kcal to kJ Converter

Convert kilocalories to kilojoules instantly, and kilojoules back to kcal. Based on the exact 1 kcal = 4.184 kJ definition.

Independently verified for accuracy

Calculator by Toolsloft ↗
Result
4.184 Kilojoules (kJ)
Conversion
1 Kilocalories (kcal) = 4.184 Kilojoules (kJ)

Convert kilocalories to kilojoules, and kilojoules back to kilocalories. Handy for reading nutrition labels that list one unit when you think in the other. Type the energy and read the result right away.

How this is calculated

One kilocalorie equals exactly 4.184 kilojoules, using the thermochemical calorie. Kilocalories are multiplied by 4.184 to get kilojoules, and the reverse divides. Both kcal and food Calories refer to the same unit, so a 2,000 Calorie diet is 8,368 kJ.

How to use

  1. Enter the energy in kilocalories.
  2. Keep the direction on kcal to kJ, or press Swap units for kJ to kcal.
  3. Read the result in kilojoules.

Examples

  • One kilocalorie: 1 kcal = 4.184 kJ
  • A 2,000 Calorie day: 2000 kcal = 8368 kJ
  • Kilojoules to kcal: 1 kJ = 0.239006 kcal

FAQ

How many kilojoules are in a kilocalorie?
One kilocalorie is exactly 4.184 kilojoules.
Is a food Calorie the same as a kilocalorie?
Yes. The Calorie printed on food labels is the kilocalorie, so the same conversion applies.

Embed this calculator

Add this free calculator to your own site. Copy the code and paste it where you want it to appear.