Kilojoules to kilowatt-hours

Type a value in kilojoules to see it in kilowatt-hours straight away, or type in the second box to convert back.

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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.

How to use it

  1. Type the value in the kilojoules box.
  2. Read the result in kilowatt-hours as you type, and pick the precision you need.
  3. Swap the direction to convert back, or copy the result.

How it is calculated

kWh = kJ × 0.0002777777778

Multiply the value in kilojoules by 0.0002777777778 to get kilowatt-hours.

Example

To convert 25 kJ to kilowatt-hours: 25 × 0.0002777777778 = 0.00694444 kWh.

Conversion table

Kilojoules (kJ)Kilowatt-hours (kWh)
10.000277778
20.000555556
30.000833333
50.00138889
100.00277778
200.00555556
250.00694444
500.0138889
1000.0277778
2500.0694444
5000.138889
1,0000.277778

About the units

Kilojoule
Exactly 1000 joules. It appears on food labels next to the calorie figure.
Kilowatt-hour
The energy used by a 1000 watt device in one hour, exactly 3.6 million joules. Electricity bills are charged in this unit.

Limits and caveats

  • Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
  • Both unit factors are exact by their official definitions.

Questions about this tool

How many kilowatt-hours are in one kilojoule?

1 kJ = 0.000277778 kWh exactly.

How do I convert kilojoules to kilowatt-hours?

Use kWh = kJ × 0.0002777777778. For example, 25 kJ = 0.00694444 kWh.

How many kilojoules are in one kilowatt-hour?

1 kWh = 3,600 kJ.

Which calorie do these converters use?

The thermochemical calorie, exactly 4.184 joules, the factor many countries use to turn kcal into kJ on food labels. The International Table calorie is 4.1868 joules, less than 0.07% larger.

What is the difference between kW and kWh?

A kilowatt is a unit of power, the rate of using energy, while a kilowatt-hour is an amount of energy. A 2 kW heater running for three hours uses 6 kWh.