How many kilojoules are in a calorie?

One food calorie (kilocalorie, kcal) equals 4.184 kilojoules. Multiply your calorie figure by 4.184 to get kilojoules.

Are these the calories shown on food labels?

Yes — nutrition labels list kilocalories (kcal), the food or large calorie, which is what this converter uses.

Does this tool send my data anywhere?

No — all calculations run locally in your browser and nothing is uploaded.

Calories to Kilojoules Converter

Convert food calories (kcal) to kilojoules, both directions.

Calories to kilojoules converter

Food energy is shown as calories (kcal) in some countries and kilojoules (kJ) in others, such as Australia. The conversion is exact: 1 kcal = 4.184 kJ, so kJ = kcal × 4.184.

Enter a value in either field and the other updates instantly. Everything runs in your browser — no data leaves your device.