How to convert kilowatt-hours to megajoules
MJ = kWh × 3.6Multiply the value in kilowatt-hours by 3.6. To go the other way, multiply by 0.2777777778 (or divide by 3.6).
A kilowatt-hour is larger than a megajoule: one kilowatt-hour contains 3.6 megajoules.
Worked examples
- 1 kilowatt-hour1 kWh × 3.6 = 3.6 MJ
- 5 kilowatt-hours5 kWh × 3.6 = 18 MJ
- 10 kilowatt-hours10 kWh × 3.6 = 36 MJ
- 20 kilowatt-hours20 kWh × 3.6 = 72 MJ
- 100 kilowatt-hours100 kWh × 3.6 = 360 MJ
Kilowatt-hours to megajoules conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Kilowatt-hours (kWh) | Megajoules (MJ) |
|---|---|
| 0.1 kWh | 0.36 MJ |
| 0.25 kWh | 0.9 MJ |
| 0.5 kWh | 1.8 MJ |
| 1 kWh | 3.6 MJ |
| 2 kWh | 7.2 MJ |
| 3 kWh | 10.8 MJ |
| 4 kWh | 14.4 MJ |
| 5 kWh | 18 MJ |
| 6 kWh | 21.6 MJ |
| 7 kWh | 25.2 MJ |
| 8 kWh | 28.8 MJ |
| 9 kWh | 32.4 MJ |
| 10 kWh | 36 MJ |
| Kilowatt-hours (kWh) | Megajoules (MJ) |
|---|---|
| 12 kWh | 43.2 MJ |
| 15 kWh | 54 MJ |
| 20 kWh | 72 MJ |
| 25 kWh | 90 MJ |
| 30 kWh | 108 MJ |
| 40 kWh | 144 MJ |
| 50 kWh | 180 MJ |
| 75 kWh | 270 MJ |
| 100 kWh | 360 MJ |
| 250 kWh | 900 MJ |
| 500 kWh | 1,800 MJ |
| 1,000 kWh | 3,600 MJ |
About the units
Kilowatt-hour (kWh)
Exactly 3.6 MJ. The unit on electricity bills; running a 1,000 W heater for an hour uses 1 kWh. One kilowatt-hour equals 3,600,000 joules (J).
Megajoule (MJ)
The megajoule (MJ) is a unit of energy in the International System of Units (SI). One megajoule equals 1,000,000 joules (J).
Frequently asked questions
How many megajoules are in one kilowatt-hour?
There are 3.6 megajoules in one kilowatt-hour, and this value is exact by definition.
How do I convert kilowatt-hours to megajoules?
Multiply the number of kilowatt-hours by 3.6. For example, 10 kWh × 3.6 = 36 MJ.
How many kilowatt-hours are in one megajoule?
One megajoule equals 0.2777777778 kilowatt-hours. That is the reverse factor, 1 ÷ 3.6.
What is 10 kilowatt-hours in megajoules?
10 kWh = 36 MJ.
Is this kWh to MJ converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.