Convert kilowatt-hours to kilojoules
Converting kilowatt-hours to kilojoules is a common energy task, whether you are checking a recipe, a spec sheet, a travel distance or a homework problem. Since 1 kWh equals 3,600 kJ, the math is a single multiplication — and this page does it for you instantly, with the formula, a table of common values and answers to the questions people ask most.
Exact factor
How to convert kilowatt-hours to kilojoules
To convert kilowatt-hours to kilojoules, multiply the number of kilowatt-hours by 3,600. For example, 10 kWh × 3,600 = 36,000 kJ.
kJ = kWh × 3,600
- Write down the value in kilowatt-hours you want to convert.
- Multiply it by 3,600 (the exact kWh→kJ factor).
- The result is your value in kilojoules. Check it below with the converter or the table.
Conversion table
Common values of kilowatt-hours and their equivalents in kilojoules:
| kWh | kJ |
|---|---|
| 1 | 3,600 |
| 2 | 7,200 |
| 3 | 10,800 |
| 4 | 14,400 |
| 5 | 18,000 |
| 10 | 36,000 |
| 20 | 72,000 |
| 25 | 90,000 |
| 50 | 180,000 |
| 100 | 360,000 |
| 250 | 900,000 |
| 500 | 1,800,000 |
About these units
Kilowatt-hour (kWh). A kilowatt-hour is the energy delivered by one kilowatt over one hour, exactly 3.6 million joules. Household electricity bills and EV batteries are measured in kWh.
Kilojoule (kJ). A kilojoule is 1,000 joules, the practical unit for food energy in Australia and Europe and for mechanical work. One kilocalorie equals 4.184 kilojoules.
Frequently asked questions
How do I convert kilowatt-hours to kilojoules?
To convert kilowatt-hours to kilojoules, multiply the number of kilowatt-hours by 3,600. For example, 10 kWh × 3,600 = 36,000 kJ. Or skip the math: type the value into the converter at the top of this page and the result updates instantly.
How many kilojoules are in 1 kilowatt-hour?
1 kWh = 3,600 kJ. That is the fixed relationship used by this converter and by international standards.
How many kilowatt-hours are in 1 kilojoule?
1 kJ = 0.000277778 kWh. If you are converting in the opposite direction, use our Kilojoule to Kilowatt-hour converter for the dedicated table and FAQ.
Is the kilowatt-hours to kilojoules conversion exact?
Yes. Both units are defined by international agreement, so the factor of 3,600 is exact. Displayed results are rounded to 6 significant digits only for readability.
What is kilowatt-hour used for?
A kilowatt-hour is the energy delivered by one kilowatt over one hour, exactly 3.6 million joules. Household electricity bills and EV batteries are measured in kWh.