Power and Energy
MJtoGJ
Convert megajoules (MJ) to gigajoules (GJ).
Factor1 MJ = 0.001 GJ
Converter
MJ
Accepts numbers or expressions, e.g. 150 + 14.7
Result
GJ
Rendered to 6 significant figures.
Formula
Formula
GJ = MJ × 0.001
Multiply any value in megajoules by 0.001 to obtain the value in gigajoules.
Worked example
Convert 1000 MJ to GJ.
- 01Start with 1000 MJ.
- 02Multiply by the conversion factor: 1000 × 0.001 = 1 GJ.
Result1000 MJ = 1 GJ
Conversion table
| MJ | GJ |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 5 | 0.005 |
| 10 | 0.01 |
| 20 | 0.02 |
| 50 | 0.05 |
| 100 | 0.1 |
| 200 | 0.2 |
| 500 | 0.5 |
| 1000 | 1 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from MJ to GJ?
1 MJ equals 0.001 GJ. To convert, multiply the value in megajoules by 0.001.
How do I convert 1 MJ to GJ?
1 MJ = 0.001 GJ. For any value, multiply by 0.001.
How do I convert GJ back to MJ?
Divide by the same factor — or equivalently, multiply by 1000. So 1 GJ = 1000 MJ.
When would I need to convert megajoule to gigajoule?
Energy conversions are needed when reconciling fuel/electrical billing, calculating thermal duties, and aligning calorimetry or HHV/LHV figures across data sources.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).