Convert Joules to Watt-hours
One joule equals 0.000278 watt-hours. Type any value to convert joules to watt-hours instantly — with a full reference table below.
Convert Joules to Watt-hours
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Conversion formula
To convert joules to watt-hours, multiply by 0.000278. One joule equals 0.000278 Wh, and one watt-hour equals 3,600 J.
Joules to Watt-hours table
About converting Joules to Watt-hours
Joules (J) and Watt-hours (Wh) are both units of energy. The exact factor is 1 J = 0.000278 Wh, so multiply by 0.000278 to go from joules to watt-hours (or divide to go back).
The conversion is exact and runs entirely in your browser. Need the reverse? Use the Watt-hours to Joules converter, or the full unit converter for every unit at once.
Frequently asked questions
How many watt-hours are in one joule?
One joule equals 0.000278 watt-hours.
How do I convert joules to watt-hours?
Multiply the number of joules by 0.000278. For example, 10 joules = 0.002778 watt-hours.
What is 5 joules in watt-hours?
5 joules is 0.001389 watt-hours.