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Energy Converter
ConverterConvert joules, calories, kilowatt-hours, BTUs, and electron volts.
About This Tool
A food calorie is actually a kilocalorie (kcal) — 4,184 joules. One kWh equals 3.6 megajoules, the energy used by a 1,000-watt device for one hour. The BTU (British Thermal Unit) is still used in HVAC ratings in the US.