This free energy converter helps you convert popular units like joules to calories, calories to joules, kJ to kcal and kWh to joules in seconds. It supports joules, kilojoules, calories, kilocalories and kilowatt-hours, making it useful for science, nutrition, electricity and everyday energy conversions.

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What units does this energy converter support?

This energy converter supports joules, kilojoules, calories, kilocalories and kilowatt-hours. You can convert in any direction, such as joules to calories, calories to joules, kJ to kcal and kWh to joules.

How do I convert joules to calories?

To convert joules to calories, divide joules by 4.184. This tool calculates it instantly and also works for kilojoules, kilocalories and kilowatt-hours.

How do I convert kWh to joules?

To convert kilowatt-hours to joules, multiply kilowatt-hours by 3,600,000. You can also use the Swap button to reverse the conversion direction instantly.

What is the difference between calories and kilocalories?

A kilocalorie equals 1000 small calories. In food labels, the word “calorie” often actually refers to kilocalories, which is why this converter includes both units.

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