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Watt-hour (Wh)

The energy of one watt sustained for one hour.

Result3,600

1 watt-hour = 3,600 joules

Watt-hour at a glance

Unit nameWatt-hour (plural: watt-hours)
SymbolWh
Quantity measuredEnergy
Measurement systemMetric
Also known aswh, watt hour
Definition exact?Yes — exact by definition

1 watt-hour in other energy units

Unit1 Wh equals
Joule3,600 J
Kilojoule3.6 kJ
Megajoule0.0036 MJ
Calorie860.42065 cal
Kilocalorie0.86042065 kcal
Kilowatt-hour0.001 kWh
Megawatt-hour0.000001 MWh
Electronvolt2.24694327 × 10²² eV
British thermal unit3.41214163 BTU
Therm0.000034121 thm
Foot-pound2,655.22374 ft·lb

Frequently asked questions

What is a watt-hour?
The energy of one watt sustained for one hour.
What is the symbol for the watt-hour?
The symbol for the watt-hour is Wh. It measures energy.
How many joules are in a watt-hour?
1 watt-hour = 3,600 joules.
How many kilojoules are in a watt-hour?
1 watt-hour = 3.6 kilojoules.
How many kilocalories are in a watt-hour?
1 watt-hour = 0.86042065 kilocalories.