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Power and Energy

GJtoMJ

Convert gigajoules (GJ) to megajoules (MJ).

Factor1 GJ = 1000 MJ

Converter

GJ

Accepts numbers or expressions, e.g. 150 + 14.7

Result
1000MJ

Rendered to 6 significant figures.

Formula

Formula
MJ = GJ × 1000

Multiply any value in gigajoules by 1000 to obtain the value in megajoules.

Worked example

Convert 1 GJ to MJ.

  1. 01Start with 1 GJ.
  2. 02Multiply by the conversion factor: 1 × 1000 = 1000 MJ.
Result1 GJ = 1000 MJ

Conversion table

GJMJ
11000
22000
55000
1010000
2020000
5050000
1001.0000e+5
2002.0000e+5
5005.0000e+5
10001.0000e+6

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from GJ to MJ?
1 GJ equals 1000 MJ. To convert, multiply the value in gigajoules by 1000.
How do I convert 1 GJ to MJ?
1 GJ = 1000 MJ. For any value, multiply by 1000.
How do I convert MJ back to GJ?
Divide by the same factor — or equivalently, multiply by 0.001. So 1 MJ = 0.001 GJ.
When would I need to convert gigajoule to megajoule?
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).

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