Convert joule to watt-hour
1 J = 0.0002777777778 Wh
1 J = 0.00027778 Wh
1 J in every energy unit
| electron volt | 6.2415e+18 eV |
| hartree | 2.2937e+17 Eh |
| kiloelectron volt | 6.2415e+15 keV |
| megaelectron volt | 6,241,500,000,000 MeV |
| gigaelectron volt | 6,241,500,000 GeV |
| nanojoule | 1,000,000,000 nJ |
| erg | 10,000,000 erg |
| teraelectron volt | 6,241,500 TeV |
| microjoule | 1,000,000 µJ |
| millijoule | 1,000 mJ |
| inch-pound | 8.8507 in·lb |
| joule | 1 J |
| foot-pound | 0.73756 ft⋅lb |
| calorie | 0.23901 cal |
| calorie (International Table) | 0.23885 cal IT |
| kilojoule | 0.001 kJ |
| BTU (thermochemical) | 0.00094845 BTU th |
| British thermal unit | 0.00094782 BTU |
| watt-hour | 0.00027778 Wh |
| kilocalorie | 0.00023901 kcal |
| megajoule | 0.000001 MJ |
| horsepower-hour | 3.7251e-07 hp·h |
| kilowatt-hour | 2.7778e-07 kWh |
| therm | 9.4782e-09 therm |
| gigajoule | 1.0000e-09 GJ |
| million BTU | 9.4782e-10 MMBTU |
| megawatt-hour | 2.7778e-10 MWh |
| ton of TNT | 2.3901e-10 t TNT |
| tonne of oil equivalent | 2.3885e-11 toe |
| terajoule | 1.0000e-12 TJ |
| gigawatt-hour | 2.7778e-13 GWh |
| kiloton of TNT | 2.3901e-13 kt TNT |
| petajoule | 1.0000e-15 PJ |
| terawatt-hour | 2.7778e-16 TWh |
| megaton of TNT | 2.3901e-16 Mt TNT |
| quad | 9.4782e-19 quad |
How the conversion works
Multiply by 0.0002777777778 to go from joule to watt-hour, or divide by it to go back. Every conversion on this site routes through the SI value (J) rather than a table of pairwise factors, so a round-trip returns exactly what you started with.
Going the other way? watt-hour to joule — 1 Wh = 3,600 J.
joule to watt-hour — common values
| 1 J | 0.00027777778 Wh |
| 2 J | 0.00055555556 Wh |
| 3 J | 0.00083333333 Wh |
| 5 J | 0.0013888889 Wh |
| 10 J | 0.0027777778 Wh |
| 15 J | 0.0041666667 Wh |
| 20 J | 0.0055555556 Wh |
| 25 J | 0.0069444444 Wh |
| 50 J | 0.013888889 Wh |
| 75 J | 0.020833333 Wh |
| 100 J | 0.027777778 Wh |
| 250 J | 0.069444444 Wh |
| 500 J | 0.13888889 Wh |
| 1000 J | 0.27777778 Wh |