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Food Energy Converter

Convert between kcal, calories, kilojoules, and joules.

Your numbers

Results

Kilocalories
500 kcal
Calories
500,000 cal
Kilojoules
2,092 kJ
Joules
2,092,000 J
Conversion

1 kcal = 4.184 kJ = 4,184 J = 1,000 cal

1 Calorie (kcal) equals 4.184 kilojoules or 4,184 joules. A food Calorie with a capital C is a kilocalorie — 1,000 small calories.

Enter a value and its unit to convert between kcal, calories, kilojoules, and joules.

How to convert food energy

To convert food energy, multiply kcal by 4.184 for kilojoules or by 4,184 for joules. Divide to go the other way.

Worked example: 500 kcal × 4.184 = 2,092 kJ.

Frequently asked questions

One kilocalorie equals 4,184 joules, or 4.184 kilojoules. One small calorie equals 4.184 joules.

On food labels, yes. A food Calorie is a kilocalorie — 1,000 small calories — so 200 kcal and 200 food Calories are identical.

Divide kilojoules by 4.184. For example, 2,000 kJ ÷ 4.184 = 478 kcal.

Results are estimates based on population averages and are not medical advice. Consult a doctor or registered dietitian nutritionist (RDN) before making large changes to your diet, especially for deficits over 2 lb (0.9 kg) per week, during pregnancy or nursing, or for anyone under 18.