Joule to Watt-hour

1 J = 0.00027777778 Wh

Value

From

Precision & format

Significant figures

Notation

1 J equals

0.0002777777778Wh

All 21 units

JouleJ
1
KilojoulekJ
0.001
MegajouleMJ
0.000001
GigajouleGJ
1 × 10⁻⁹
MillijoulemJ
1,000
Calorie (thermochemical)cal
exactly 4.184 J
0.2390057361
Kilocalorie (thermochemical)kcal
food Calorie
0.0002390057361
Calorie (IT)cal (IT)
International Table
0.2388458966
Kilocalorie (IT)kcal (IT)
0.0002388458966
Watt-hourWh
0.0002777777778
Kilowatt-hourkWh
2.777777778 × 10⁻⁷
Megawatt-hourMWh
2.777777778 × 10⁻¹⁰
BTU (IT)BTU
International Table
0.0009478171203
BTU (thermochemical)BTU (th)
0.0009484514148
Therm (US)thm
100 000 BTU
9.48043428 × 10⁻⁹
Foot-poundft·lbf
0.7375621493
Ergerg
10,000,000
ElectronvolteV
6.241509074 × 10¹⁸
KiloelectronvoltkeV
6.241509074 × 10¹⁵
MegaelectronvoltMeV
6,241,509,074,000
Tonne of oil equivalenttoe
2.388458966 × 10⁻¹¹

Joule to Watt-hour table

Common Joule values converted to Watt-hour
Joule (J)	Watt-hour (Wh)
1	0.00027777778
2	0.00055555556
5	0.0013888889
10	0.0027777778
20	0.0055555556
50	0.013888889
100	0.027777778
250	0.069444444
500	0.13888889
1,000	0.27777778

How the conversion works

Multiply the joule figure by 0.0002777777778 to get watt-hour. Every factor on this site is anchored to the SI base unit for energy, so the same number is used everywhere it appears.

Going the other way, 1 Wh = 3,600 J — see watt-hour to joule.

See all 21 energy units →