Megajoules: conversions & definition
One megajoule equals one million joules or 1,000 kilojoules. Converting an energy amount does not account for fuel quality, appliance losses or conversion efficiency.
Choose the unit you need
Each row converts one MJ. Open a converter to enter any value and see its formula, worked example and reference table. Results below are rounded to 10 significant digits.
| Convert to | Equivalent value | Calculator |
|---|---|---|
| Joules (J) | ≈ 1,000,000 | Convert MJ to J |
| Kilojoules (kJ) | ≈ 1,000 | Convert MJ to kJ |
| Watt-hours (Wh) | ≈ 277.7777778 | Convert MJ to Wh |
| Kilowatt-hours (kWh) | ≈ 0.2777777778 | Convert MJ to kWh |
| Kilocalories (kcal th) | ≈ 239.0057361 | Convert MJ to kcal th |
| Millijoules (mJ) | ≈ 1,000,000,000 | Convert MJ to mJ |
| Microjoules (µJ) | ≈ 1e+12 | Convert MJ to µJ |
| Nanojoules (nJ) | ≈ 1e+15 | Convert MJ to nJ |
| Gigajoules (GJ) | ≈ 0.001 | Convert MJ to GJ |
| Centijoules (cJ) | ≈ 100,000,000 | Convert MJ to cJ |
| Decijoules (dJ) | ≈ 10,000,000 | Convert MJ to dJ |
| Hectojoules (hJ) | ≈ 10,000 | Convert MJ to hJ |
| Decajoules (daJ) | ≈ 100,000 | Convert MJ to daJ |
| Picojoules (pJ) | ≈ 1e+18 | Convert MJ to pJ |
| Terajoules (TJ) | ≈ 0.000001 | Convert MJ to TJ |
| Femtojoules (fJ) | ≈ 1e+21 | Convert MJ to fJ |
| Petajoules (PJ) | ≈ 1e-9 | Convert MJ to PJ |
| Attojoules (aJ) | ≈ 1e+24 | Convert MJ to aJ |
| Exajoules (EJ) | ≈ 1e-12 | Convert MJ to EJ |
| Zeptojoules (zJ) | ≈ 1e+27 | Convert MJ to zJ |
| Zettajoules (ZJ) | ≈ 1e-15 | Convert MJ to ZJ |
| Yoctojoules (yJ) | ≈ 1e+30 | Convert MJ to yJ |
| Yottajoules (YJ) | ≈ 1e-18 | Convert MJ to YJ |
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