Joules to Calories Converter

Joules to Calories Converter

Calories (cal)
—
Kilocalories (kcal)
—
1 calorie = 4.184 joules · 1 kcal = 4184 joules

How to convert joules to calories

To convert joules to calories, divide by 4.184. For example, 1000 J ÷ 4.184 = 239.006 calories. To convert joules to kilocalories (food Calories), divide by 4184.

Going the other way — to convert calories to joules — multiply by 4.184. So 100 calories × 4.184 = 418.4 joules.

Important note: food Calories (with a capital C) are actually kilocalories. So when a food label says 200 Calories, it means 200 kcal = 200,000 small calories = 836,800 joules.

Joules to calories conversion table

Joules (J) Calories (cal) Kilocalories (kcal)
1 J0.239 cal0.000239 kcal
10 J2.390 cal0.00239 kcal
100 J23.901 cal0.0239 kcal
500 J119.503 cal0.1195 kcal
1000 J (1 kJ)239.006 cal0.239 kcal
4184 J1000 cal1 kcal
10,000 J2390.06 cal2.390 kcal
100,000 J23,900.6 cal23.901 kcal

Frequently asked questions

How many joules is 1 calorie?
1 calorie = 4.184 joules. 1 kilocalorie (food Calorie) = 4184 joules = 4.184 kilojoules.
What is the difference between calories and Calories?
A small calorie (cal) is the energy to heat 1g of water by 1°C. A food Calorie (Cal or kcal) = 1000 small calories. Food labels use Calories (kcal) not small calories.
How many joules is 100 calories?
100 cal = 418.4 joules. 100 kcal (food Calories) = 418,400 joules = 418.4 kilojoules.
How many kilojoules is 1 kcal?
1 kcal = 4.184 kilojoules. Many food labels in Australia and Europe show kilojoules instead of Calories.
How many joules is 2000 calories?
2000 kcal (the average daily intake) = 8,368,000 joules = 8368 kilojoules. Calculation: 2000 × 4184 = 8,368,000 J.