How many megajoules are in a kilowatt-hour?

One kilowatt-hour equals 3.6 megajoules exactly, because 1000 watts running for 3600 seconds is 3,600,000 joules, or 3.6 MJ.

How do I convert MJ back to kWh?

Divide megajoules by 3.6. For example, 18 MJ equals 18 ÷ 3.6 = 5 kWh. This tool does it for you when you pick the MJ to kWh direction.

Is anything sent to a server?

No — the conversion runs entirely in your browser and no data is uploaded.

kWh to MJ Converter — Gera Tools

kWh to MJ — the exact energy conversion

One kilowatt-hour equals 3.6 megajoules exactly. This converter turns kilowatt-hours (kWh), the unit on your electricity bill, into megajoules (MJ), the SI energy unit, and back again.

The factor is exact: 1 kW × 1 hour = 1000 W × 3600 s = 3,600,000 J = 3.6 MJ. So a 12 kWh daily household usage is 12 × 3.6 = 43.2 MJ.

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