Energy Converter
Compare energy units used in science, nutrition, heating, and electricity, including joules, calories, BTU, watt-hours, and kilowatt-hours.
Results update as you type, and you can swap the source and target units at any time.
Quick Starts
Common Conversions
1 kWh = 3600 kJ
Kilowatt-hour to Kilojoule
100 kcal = 418.4 kJ
Kilocalorie to Kilojoule
1 BTU = 1055.05585262 J
British Thermal Unit to Joule
500 Wh = 0.5 kWh
Watt-hour to Kilowatt-hour
1 MJ = 0.277777777778 kWh
Megajoule to Kilowatt-hour
1 ft·lbf = 1.355817948331 J
Foot-pound to Joule
Units In This Converter
J
Joule
kJ
Kilojoule
MJ
Megajoule
cal
Calorie
kcal
Kilocalorie
Wh
Watt-hour
kWh
Kilowatt-hour
BTU
British Thermal Unit
ft·lbf
Foot-pound
Using This Tool
Use this converter to compare energy values across physics, nutrition, heating, and electricity, including joules, kilojoules, calories, watt-hours, kilowatt-hours, and BTU.
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FAQ
One kilowatt-hour is exactly 3,600,000 joules.
One kilocalorie is exactly 4.184 kilojoules.