Convert megajoules to gigajoules
1 MJ = 0.001 GJ — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
0.001GJ
As a fraction: 1/1000
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1 MJ = 0.001 GJ
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 gigajoules
Multiply the number of megajoules by 0.001 to get gigajoules.
The exact factor is 0.001 — as a fraction, 1/1000.
Megajoule to Gigajoule conversion table
| Megajoules (MJ) | Gigajoules (GJ) |
|---|---|
| 1 MJ | 0.001 |
| 2 MJ | 0.002 |
| 3 MJ | 0.003 |
| 5 MJ | 0.005 |
| 10 MJ | 0.01 |
| 20 MJ | 0.02 |
| 25 MJ | 0.025 |
| 50 MJ | 0.05 |
| 100 MJ | 0.1 |
| 250 MJ | 0.25 |
| 500 MJ | 0.5 |
| 1000 MJ | 1 |
Gigajoule to Megajoule conversion table
| Gigajoules (GJ) | Megajoules (MJ) |
|---|---|
| 1 GJ | 1000 |
| 2 GJ | 2000 |
| 3 GJ | 3000 |
| 5 GJ | 5000 |
| 10 GJ | 10 000 |
| 20 GJ | 20 000 |
| 25 GJ | 25 000 |
| 50 GJ | 50 000 |
| 100 GJ | 100 000 |
| 250 GJ | 250 000 |
| 500 GJ | 500 000 |
| 1000 GJ | 1 000 000 |
Frequently asked
How many gigajoules are in a megajoule?
One megajoule equals 0.001 gigajoules (MJ → GJ). That figure is exact, not rounded.
How do you convert megajoules to gigajoules?
Multiply the number of megajoules by 0.001 to get gigajoules.
What is 1 GJ in megajoules?
One gigajoule is 1000 megajoules.
What is 10 MJ in GJ?
10 MJ = 0.01 GJ.