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gigajoule to megawatt-hour

Convert gigajoule (GJ) to megawatt-hour (MWh). Use an editable energy converter, conversion formula, and reference table.

0.2777777778

1 GJ = 0.2777777778 MWh

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Conversion formula

MWh = GJ × 0.2777777778

One gigajoule equals 0.2777777778 megawatt-hour. Multiply your value in gigajoule by this factor to get megawatt-hour. For the reverse conversion, divide by the same factor.

Worked example

To convert 5 gigajoule:
5 × 0.2777777778 = 1.388888889 MWh

Conversion table

gigajoule (GJ)megawatt-hour (MWh)
0.010.002777777778
0.10.02777777778
10.2777777778
20.5555555556
51.388888889
102.777777778
256.944444444
5013.88888889
10027.77777778
1000277.7777778

About these measurements

Energy can be transferred through work, heating, or electrical processes.

The base reference used here is the joule. One gigajoule is 1,000,000,000 base units; one megawatt-hour is 3,600,000,000 base units.

Important distinctions

Calorie and BTU definitions vary. These pages label thermochemical calories and International Table BTUs explicitly.

Precision

The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.

Common questions

How do I convert GJ to MWh?

Multiply the quantity in GJ by 0.2777777778. You can also type the value into the converter above.

Can I reverse the conversion?

Yes. Use the swap button or open the megawatt-hour to gigajoule converter.

Reference

NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.

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