Energy and work unit converter
Convert between J, kJ, MJ, Wh, kWh, BTU and more, with formulas and tables.
Popular energy and work conversions
- kWh to MJ
- MJ to kWh
- BTU to kJ
- kJ to BTU
- kWh to BTU
- BTU to kWh
- therm to kWh
- J to ft·lbf
- ft·lbf to J
- kcal to kJ
Conversion matrix
Each cell is how many of the column unit equal 1 of the row unit. Tap a value for the full table.
The units
- J (joules): The SI unit of energy: one newton metre.
- kJ (kilojoules): Thermal and mechanical energy in engineering calculations.
- MJ (megajoules): Fuel energy and large thermal loads.
- Wh (watt-hours): Battery and small-load energy.
- kWh (kilowatt-hours): Electricity billing.
- BTU (British thermal units (IT)): US heating, cooling and fuel energy.
- therm (therms (US)): Natural gas billing in the US: 100,000 BTU (59 °F), or 105.48 MJ.
- cal (calories (thermochemical)): Small heat quantities in science work.
- kcal (kilocalories): Food energy and older metric heat units.
- ft·lbf (foot-pounds-force): US mechanical work and impact energy.
The BTU used here is the International Table BTU (1,055.056 J). A foot-pound of energy (ft·lbf) is the same dimension as a lbf·ft of torque, but the two are different physical quantities.
All energy and work conversions
- J to kJ
- J to MJ
- J to Wh
- J to kWh
- J to BTU
- J to therm
- J to cal
- J to kcal
- J to ft·lbf
- kJ to J
- kJ to MJ
- kJ to Wh
- kJ to kWh
- kJ to BTU
- kJ to therm
- kJ to cal
- kJ to kcal
- kJ to ft·lbf
- MJ to J
- MJ to kJ
- MJ to Wh
- MJ to kWh
- MJ to BTU
- MJ to therm
- MJ to cal
- MJ to kcal
- MJ to ft·lbf
- Wh to J
- Wh to kJ
- Wh to MJ
- Wh to kWh
- Wh to BTU
- Wh to therm
- Wh to cal
- Wh to kcal
- Wh to ft·lbf
- kWh to J
- kWh to kJ
- kWh to MJ
- kWh to Wh
- kWh to BTU
- kWh to therm
- kWh to cal
- kWh to kcal
- kWh to ft·lbf
- BTU to J
- BTU to kJ
- BTU to MJ
- BTU to Wh
- BTU to kWh
- BTU to therm
- BTU to cal
- BTU to kcal
- BTU to ft·lbf
- therm to J
- therm to kJ
- therm to MJ
- therm to Wh
- therm to kWh
- therm to BTU
- therm to cal
- therm to kcal
- therm to ft·lbf
- cal to J
- cal to kJ
- cal to MJ
- cal to Wh
- cal to kWh
- cal to BTU
- cal to therm
- cal to kcal
- cal to ft·lbf
- kcal to J
- kcal to kJ
- kcal to MJ
- kcal to Wh
- kcal to kWh
- kcal to BTU
- kcal to therm
- kcal to cal
- kcal to ft·lbf
- ft·lbf to J
- ft·lbf to kJ
- ft·lbf to MJ
- ft·lbf to Wh
- ft·lbf to kWh
- ft·lbf to BTU
- ft·lbf to therm
- ft·lbf to cal
- ft·lbf to kcal