Energy and work converter

Convert between every common energy unit — physics joules, dietary calories, electricity-bill kilowatt-hours, heating BTUs and more. Energy and work share units (both are force × distance).

Converter

All units
UnitValue

Common values

  • 1 kcal (food cal) = 4.184 kJ
  • 1 kWh = 3.6 MJ = 3412 BTU
  • 1 BTU = 1055 J ≈ heat to raise 1 lb of water by 1 °F
  • 1 eV = 1.602 × 10⁻¹⁹ J (atomic-scale energy)

FAQ

Calorie vs kilocalorie?

The "Calorie" on food labels is actually the kilocalorie (1000 small calories). 1 food Cal = 1 kcal = 4.184 kJ.

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