Megajoules to kWh Converter
Convert megajoules to kilowatt-hours — 3.6 MJ make one kWh. Results update as you type; exact factors shown.
One megajoule is 0.2778 kilowatt-hours — see the exact factor, not a rounded rule of thumb.
How the megajoules to kwh converter works
Energy converts through the joule. A thermochemical calorie is exactly 4.184 J, so a food Calorie (kcal) is 4.184 kJ. A kilowatt-hour is exactly 3.6 MJ. A BTU is 1,055.056 J and a US therm is 100,000 BTU.
Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.
Common energy conversions
| From | To | Units |
|---|---|---|
| 1 MJ | 0.2778 kWh | megajoule to kilowatt-hours |
| 3.6 MJ | 1 kWh | megajoules to kilowatt-hours |
| 5 MJ | 1.3889 kWh | megajoules to kilowatt-hours |
| 10 MJ | 2.7778 kWh | megajoules to kilowatt-hours |
| 18 MJ | 5 kWh | megajoules to kilowatt-hours |
| 25 MJ | 6.9444 kWh | megajoules to kilowatt-hours |
| 36 MJ | 10 kWh | megajoules to kilowatt-hours |
| 50 MJ | 13.8889 kWh | megajoules to kilowatt-hours |
| 100 MJ | 27.7778 kWh | megajoules to kilowatt-hours |
| 200 MJ | 55.5556 kWh | megajoules to kilowatt-hours |
| 500 MJ | 138.8889 kWh | megajoules to kilowatt-hours |
| 1,000 MJ | 277.7778 kWh | megajoules to kilowatt-hours |
Units in this converter and their exact factors
| Unit | Symbol | One unit in joules |
|---|---|---|
| joule | J | 1 joule |
| kilojoule | kJ | 1,000 joule |
| megajoule | MJ | 1,000,000 joule |
| calorie (thermochemical) | cal | 4.184 joule |
| kilocalorie (food Calorie) | kcal | 4,184 joule |
| watt-hour | Wh | 3,600 joule |
| kilowatt-hour | kWh | 3,600,000 joule |
| British thermal unit | BTU | 1,055.05585262 joule |
| therm (US) | thm | 105,505,585.262 joule |
| foot-pound | ft·lb | 1.3558179483 joule |
FAQFrequently asked questions about energy conversion
How many MJ in a kWh?
Exactly 3.6.
Why does my gas bill use MJ and my electricity bill kWh?
Convention — Australian gas is billed in megajoules, electricity in kilowatt-hours. They measure the same thing.
What is 100 MJ in kWh?
27.8 kWh.
Which is bigger?
A kilowatt-hour, by a factor of 3.6.
What is 1 MJ?
A million joules, or 0.278 kWh.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Measurement Institute (NMI) — Australia's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.