Convert megajoules to watt-hours
1 MJ = 277.777777778 Wh — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
277.777 777 778Wh
As a fraction: 2500/9
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1 MJ = 277.777777778 Wh
Show this value in all 39 energy & work units
- Petajoules PJ 1e-9
- Terajoules TJ 0.000 001
- Gigajoules GJ 0.001
- Megajoules MJ 1
- Kilojoules kJ 1000
- Joules J 1 000 000
- Millijoules mJ 1 000 000 000
- Microjoules µJ 1 000 000 000 000
- Nanojoules nJ 1 000 000 000 000 000
- Watt-hours Wh 277.777 777 778
- Kilowatt-hours kWh 0.277 777 777 778
- Megawatt-hours MWh 0.000 277 777 777 778
- Gigawatt-hours GWh 0.000 000 277 777 777 778
- Terawatt-hours TWh 2.77777777778e-10
- Calorie (thermochemical)s cal 239 005.736 138
- Kilocalories kcal 239.005 736 138
- Calorie (IT)s cal (IT) 238 845.896 627
- Kilocalorie (IT)s kcal (IT) 238.845 896 627
- British thermal units BTU 947.817 120 313
- BTU (thermochemical)s BTU (th) 948.451 652 677
- Million BTUs MMBTU 0.000 947 817 120 313
- Therm (US)s thm 0.009 480 434 279 73
- Therm (EC)s thm (EC) 0.009 478 169 879 13
- Electronvolts eV 6.24150907446e+24
- Kiloelectronvolts keV 6.24150907446e+21
- Megaelectronvolts MeV 6.24150907446e+18
- Gigaelectronvolts GeV 6 241 509 074 460 000
- Teraelectronvolts TeV 6 241 509 074 460
- Ergs erg 10 000 000 000 000
- Foot-pounds ft·lbf 737 562.149 277
- Inch-pounds in·lbf 8 850 745.791 33
- Foot-poundals ft·pdl 23 730 360.4042
- Horsepower-hours hp·h 0.372 506 135 999
- Tonne of TNTs t TNT 0.000 239 005 736 138
- Kiloton of TNTs kt TNT 0.000 000 239 005 736 138
- Megaton of TNTs Mt TNT 2.39005736138e-10
- Hartrees Eₕ 2.2937122784e+23
- Rydbergs Ry 4.58742455679e+23
- Quads quad 9.47817120313e-13
Every row is Megajoule (MJ) converted through the joule, in exact rational arithmetic.
How to convert megajoules to watt-hours
Multiply the number of megajoules by 277.777777778 to get watt-hours.
Megajoule to Watt-hour conversion table
| Megajoules (MJ) | Watt-hours (Wh) |
|---|---|
| 1 MJ | 277.777 78 |
| 2 MJ | 555.555 56 |
| 3 MJ | 833.333 33 |
| 5 MJ | 1388.8889 |
| 10 MJ | 2777.7778 |
| 20 MJ | 5555.5556 |
| 25 MJ | 6944.4444 |
| 50 MJ | 13 888.889 |
| 100 MJ | 27 777.778 |
| 250 MJ | 69 444.444 |
| 500 MJ | 138 888.89 |
| 1000 MJ | 277 777.78 |
Watt-hour to Megajoule conversion table
| Watt-hours (Wh) | Megajoules (MJ) |
|---|---|
| 1 Wh | 0.0036 |
| 2 Wh | 0.0072 |
| 3 Wh | 0.0108 |
| 5 Wh | 0.018 |
| 10 Wh | 0.036 |
| 20 Wh | 0.072 |
| 25 Wh | 0.09 |
| 50 Wh | 0.18 |
| 100 Wh | 0.36 |
| 250 Wh | 0.9 |
| 500 Wh | 1.8 |
| 1000 Wh | 3.6 |
Frequently asked
How many watt-hours are in a megajoule?
One megajoule equals 277.7777778 watt-hours (MJ → Wh). That figure is exact, not rounded.
How do you convert megajoules to watt-hours?
Multiply the number of megajoules by 277.777777778 to get watt-hours.
What is 1 Wh in megajoules?
One watt-hour is 0.0036 megajoules.
What is 10 MJ in Wh?
10 MJ = 2777.7778 Wh.