How many calories are in a joule?

One calorie (thermochemical) equals 4.184 joules. One food calorie (kilocalorie) equals 4,184 joules.

What is a kilowatt-hour?

A kilowatt-hour (kWh) is a unit of energy equal to 3,600,000 joules. It measures the energy consumed by a 1,000-watt device running for one hour.

How do I convert BTU to joules?

One BTU (British Thermal Unit) equals approximately 1,055.06 joules. BTU is commonly used for heating and cooling systems.

What is an electronvolt?

An electronvolt (eV) is a tiny unit of energy equal to 1.602 × 10⁻¹⁹ joules, used in particle physics and quantum mechanics.

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Energy Converter

Convert between joules, calories, kilowatt-hours, BTU, and electronvolts.

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About Energy Conversion

1 calorie = 4.184 joules. 1 kilocalorie (food calorie) = 4,184 J. 1 kWh = 3,600,000 J. 1 BTU = 1,055 J. Energy units bridge physics, nutrition, and engineering.