Energy Converter
Convert joules, calories, kilowatt-hours, watt-hours, and other energy units.
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Frequently asked questions
Which energy units can I switch between?
Joule, kilojoule, calorie, kilocalorie, watt-hour, kilowatt-hour, and BTU. The calorie uses the thermochemical value of 4.184 J.
Is the Calorie on a food label the same as a calorie here?
No. Nutrition labels use the kilocalorie, so 300 kcal on a package is 300,000 of the small calories in this table.