Energy conversion

Convert Joule to Watt-hour

1 joule (J) equals 0.000277777778 watt-hour (Wh). Enter any value below to convert from J to Wh.

Enter a value and choose units. Results update instantly.

1 J = 0.0002777778 Wh

All Energy units

From 1 J
UnitValue
Joule J 1
Kilojoule kJ 0.001
Thermochemical calorie cal 0.2390057361
Kilocalorie kcal 0.0002390057
Watt-hour Wh 0.0002777778
Kilowatt-hour kWh 0.0000002778
BTU (International Table) BTUₕᵀ 0.0009478171
Foot-pound ft·lb 0.7375621493
Electronvolt eV 6.2415090745e18
Recent conversions
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Formula

J to Wh conversion formula

Use this relationship for a direct conversion:

Wh = J x 0.000277777778

Worked example

2 J = 0.0005555556 Wh.

The thermochemical calorie and International Table BTU are named explicitly to avoid ambiguous legacy definitions.

Quick reference

Joule to Watt-hour table

Joule (J)Watt-hour (Wh)
0.010.0000027778
0.10.0000277778
10.0002777778
20.0005555556
50.0013888889
100.0027777778
250.0069444444
500.0138888889
1000.0277777778
1,0000.2777777778

From unit

About the joule

The SI unit of energy, equal to one newton meter.

Symbol: J

To unit

About the watt-hour

The energy from one watt sustained for one hour.

Symbol: Wh

Keep converting

Related conversions

Watt-hour to JouleReverse this conversion Joule to KilojouleJ to kJJoule to Thermochemical calorieJ to calJoule to KilocalorieJ to kcalJoule to Kilowatt-hourJ to kWhJoule to BTU (International Table)J to BTUₕᵀJoule to Foot-poundJ to ft·lb

Source

Conversion standard

Definitions are checked against NIST SP 811: Energy units. Calculations use full internal precision before display rounding.

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Questions

J to Wh FAQ

How do you convert joule to watt-hour?

Use the formula Wh = J x 0.000277777778. 1 joule (J) equals 0.000277777778 watt-hour (Wh).

Is the J to Wh conversion exact?

Both unit definitions use exact factors. Only the displayed decimal may be rounded.