How to convert joules to kilowatt hours
To convert joules to kilowatt hours, multiply by 2.77777778e-7. Energy conversions connect nutrition, electricity bills, heating systems and physics.
Joule to Kilowatt-hour conversion table
| Joule (J) | Kilowatt-hour (kWh) |
|---|---|
| 0.1 J | 2.77777778e-8 kWh |
| 0.5 J | 1.38888889e-7 kWh |
| 1 J | 2.77777778e-7 kWh |
| 2 J | 5.55555556e-7 kWh |
| 3 J | 8.33333333e-7 kWh |
| 4 J | 0.00000111111111111 kWh |
| 5 J | 0.00000138888888889 kWh |
| 10 J | 0.00000277777777778 kWh |
| 20 J | 0.00000555555555556 kWh |
| 25 J | 0.00000694444444444 kWh |
| 50 J | 0.0000138888888889 kWh |
| 100 J | 0.0000277777777778 kWh |
| 500 J | 0.000138888888889 kWh |
| 1,000 J | 0.000277777777778 kWh |
About the units
Joule (J)
The joule is the SI unit of energy, the work done by one newton over one meter.
Kilowatt-hour (kWh)
A kilowatt-hour equals 3.6 million joules and is the unit on electricity bills.
How to use this converter
- Type the number of joules (J) in the input box.
- The result in kilowatt hours appears instantly — no button needed.
- See the same value in every other energy unit just below.
- Use “Swap units” to convert kilowatt hours back to joules.
When you’ll use the joule to kilowatt-hour conversion
Converting joules to kilowatt hours comes up more often than you might expect — for example when comparing fuel and battery capacities, understanding your electricity bill in kWh, or comparing food energy in kcal and kJ. Type your number once and you get the exact answer plus every related unit, so you don’t need to convert twice.
💡 For a quick estimate in your head, multiply by about 2.8e-7 (the exact factor is 2.77777778e-7).
Watch out for these mix-ups
- Food “Calories” are kilocalories (kcal), not small calories.
- kW is power (a rate); kWh is energy (an amount).
Tips for better results
- Double-check which system a unit belongs to (for example US vs UK gallons).
- Use the swap button to convert in the opposite direction instantly.
- Bookmark the conversions you use most — each pair has its own page.
Frequently asked questions
How many kilowatt hours are in one joule?
One joule equals 2.77777778e-7 kilowatt hours. 2.77777778e-7 is the exact factor used by this converter.
How do I convert joules to kilowatt hours?
Multiply the value in joules by 2.77777778e-7. To go the other way, multiply kilowatt hours by 3,600,000.
What is 10 J in kWh?
10 J = 0.00000277777777778 kWh. Also, 5 J = 0.00000138888888889 kWh and 100 J = 0.0000277777777778 kWh.
What is the difference between a joule and a kilowatt-hour?
The joule is the SI unit of energy, the work done by one newton over one meter. A kilowatt-hour equals 3.6 million joules and is the unit on electricity bills.
Is this tool free and private?
Yes — the Joule to Kilowatt-hour is completely free with no sign-up, and it runs entirely in your browser, so the values you enter are never uploaded to our servers.
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