Convert gigajoules to megajoules
1 GJ = 1000 MJ — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
1000MJ
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1 GJ = 1000 MJ
Show this value in all 39 energy & work units
- Petajoules PJ 0.000 001
- Terajoules TJ 0.001
- Gigajoules GJ 1
- Megajoules MJ 1000
- Kilojoules kJ 1 000 000
- Joules J 1 000 000 000
- Millijoules mJ 1 000 000 000 000
- Microjoules µJ 1 000 000 000 000 000
- Nanojoules nJ 1e+18
- Watt-hours Wh 277 777.777 778
- Kilowatt-hours kWh 277.777 777 778
- Megawatt-hours MWh 0.277 777 777 778
- Gigawatt-hours GWh 0.000 277 777 777 778
- Terawatt-hours TWh 0.000 000 277 777 777 778
- 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 0.947 817 120 313
- Therm (US)s thm 9.480 434 279 73
- Therm (EC)s thm (EC) 9.478 169 879 13
- Electronvolts eV 6.24150907446e+27
- Kiloelectronvolts keV 6.24150907446e+24
- Megaelectronvolts MeV 6.24150907446e+21
- Gigaelectronvolts GeV 6.24150907446e+18
- Teraelectronvolts TeV 6 241 509 074 460 000
- Ergs erg 1e+16
- Foot-pounds ft·lbf 737 562 149.277
- Inch-pounds in·lbf 8 850 745 791.33
- Foot-poundals ft·pdl 23 730 360 404.2
- Horsepower-hours hp·h 372.506 135 999
- Tonne of TNTs t TNT 0.239 005 736 138
- Kiloton of TNTs kt TNT 0.000 239 005 736 138
- Megaton of TNTs Mt TNT 0.000 000 239 005 736 138
- Hartrees Eₕ 2.2937122784e+26
- Rydbergs Ry 4.58742455679e+26
- Quads quad 9.47817120313e-10
Every row is Gigajoule (GJ) converted through the joule, in exact rational arithmetic.
How to convert gigajoules to megajoules
Multiply the number of gigajoules by 1000 to get megajoules.
The exact factor is 1000 .
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 |
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 |
Frequently asked
How many megajoules are in a gigajoule?
One gigajoule equals 1000 megajoules (GJ → MJ). That figure is exact, not rounded.
How do you convert gigajoules to megajoules?
Multiply the number of gigajoules by 1000 to get megajoules.
What is 1 MJ in gigajoules?
One megajoule is 0.001 gigajoules.
What is 10 GJ in MJ?
10 GJ = 10 000 MJ.