Ans

Unit converter

Kilowatt-hours to megajoules.

Convert kW·h to MJ and MJ to kW·h. Type in either box and the other follows. Electricity is billed in kilowatt-hours and gas in megajoules or kilowatt-hours; one kWh is exactly 3.6 MJ.

kW·h → MJExact definition
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Kilowatt-hours to megajoules — common values, to 6 significant figures.
kW·hMJ
1 kW·h3.6 MJ
2 kW·h7.2 MJ
5 kW·h18 MJ
10 kW·h36 MJ
20 kW·h72 MJ
50 kW·h180 MJ
100 kW·h360 MJ
250 kW·h900 MJ
500 kW·h1800 MJ
1000 kW·h3600 MJ
1 kW·h=3.6 MJ 1 MJ=0.2777777778 kW·h

Definitions

  • The kilowatt-hour is 3.6 MJ — one kilowatt sustained for an hour, and the unit an electricity meter bills in.
  • The megajoule is a million joules. Domestic gas bills convert metered volume into MJ or kWh.
  • This conversion is exact by definition. 1 kW·h = 3.6 MJ.
  • The food calorie is the kilocalorie: 1 kcal = 1000 cal. Nutrition labels marked "calories" mean kcal.

How it works

One direction multiplies and the other divides by the same number, so nothing is lost by going back and forth.

The value passes through J, the unit every other energy unit on the site is defined against, rather than a number written into this page on its own. That is why the figure here, the figure in the table above and the general energy converter always agree.

Display precision limits significant figures rather than decimal places, because one fixed number of decimals is useless across a range this wide. Very large and very small results switch to scientific notation with a proper superscript exponent. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: how many megajoules in a kilowatt-hour (3.6), how many kilowatt-hours in a megajoule (0.277778), and what 100 kW·h is in megajoules (360 MJ).

From the maker of Ans — a scientific calculator you can own. Same idea: a proper instrument, nothing in the way.