Energy Converter
Convert between joules, calories, watt-hours, kWh and BTU.
Enter values
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Step by step
The formula
result = value × (factorₓ / factorᵧ)
Every unit here measures the same thing: the capacity to do work. A joule is small, a kilowatt-hour is 3.6 million of them. Note that the "calorie" on food labels is really a kilocalorie — 1,000 of the scientific kind.
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Example calculations
Common questions this calculator answers — select one to load its values.
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Frequently asked questions
How many joules in a calorie?+
One (thermochemical) calorie equals 4.184 joules.
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