Convert Kilojoules to Watt-hours
kJ to Wh · energy conversion
What are kilojoules and watt-hours?
A kilojoule is 1,000 joules, used for food energy outside the US. A watt-hour is the energy of one watt sustained for one hour, equal to 3,600 J. For reference: a food Calorie is one kilocalorie (4,184 J), and home electricity is billed in kilowatt-hours.
How to convert kilojoules to watt-hours
1 kJ = 0.277778 Wh. To convert, multiply the number of kilojoules by 0.277778. For example, 5 kJ = 1.38889 Wh, and 20 kJ = 5.55556 Wh. To go the other way, multiply watt-hours by 3.6 (since 1 Wh = 3.6 kJ).
Kilojoules to Watt-hours conversion table
| Kilojoules (kJ) | Watt-hours (Wh) |
|---|---|
| 1 | 0.277778 |
| 10 | 2.77778 |
| 100 | 27.7778 |
| 500 | 138.889 |
| 1,000 | 277.778 |
| 2,000 | 555.556 |
| 5,000 | 1,388.89 |
FAQ
What is 1 kJ in Wh?
1 kJ = 0.277778 Wh. To convert any amount, multiply the number of kilojoules by 0.277778.
How do I convert watt-hours back to kilojoules?
Go the other way: 1 Wh = 3.6 kJ, so multiply watt-hours by 3.6 to get kilojoules.
Is a kilojoule bigger than a watt-hour?
No — 1 kJ is the smaller unit, equal to 0.277778 Wh (it takes 3.6 kJ to make one Wh).
Are these energy conversions exact?
They use the standard internationally-defined conversion factors. Results are rounded to six significant figures for readability, which is accurate enough for everyday and most technical use.