Energy Converter
Convert between 10 units of energy — joules, kilojoules, megajoules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, electronvolts, and foot-pounds.
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About the Energy Converter
Energy is the capacity to do work, measured in joules (J) in the SI system. Different fields use their own preferred units: food science uses kilocalories (kcal), electricity billing uses kilowatt-hours (kWh), and atomic physics uses electronvolts (eV). Understanding energy unit conversions is fundamental to physics, engineering, nutrition, and environmental science.
Quick facts
- ›One kilowatt-hour (kWh) equals 3,600,000 joules (3.6 MJ)
- ›A dietary Calorie (kcal) equals 4,184 joules
- ›The atomic bomb dropped on Hiroshima released ~6.3 × 10¹³ joules of energy
- ›The energy in one litre of petrol is approximately 34.2 MJ
Common uses: Physics, electrical engineering, nutrition, thermodynamics, environmental science