Energy Converter
Convert energy between joules, kilojoules, megajoules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, electronvolts, and ergs, with all equivalents shown at once.
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Energy
Convert energy between SI, thermal, electrical, and scientific units
Enter a value and choose a unit to see all equivalents at once — joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, electronvolts, foot-pounds, and ergs.
SI
Thermal
Electrical
Other
Quick reference
- 1 cal = 4.184 J
- 1 kcal = 4,184 J
- 1 kWh = 3,600,000 J
- 1 BTU = 1,055.06 J
- 1 eV = 1.602 × 10−19 J
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