Convert joules to watt-hours quickly and accurately using this free online converter
Used in nutrition labels, physics, and electricity consumption.
💡 Calories (kcal) are used in food; joules in science; kWh in electricity.
Wh = J × 0.00027778
Example: 1 J × 0.00027778 = 0.00027778 Wh
Use kcal for food; kWh for energy consumption; joules for science.
Common uses: nutrition, electricity bills, and scientific calculations.
How do I convert J to Wh?
Multiply the value in Joules by 0.00027778. For example: 10 J = 0.00277778 Wh.
When should I use Watt-hours instead of Joules?
Use kcal for food; kWh for energy consumption; joules for science.
Is this converter accurate?
Yes. We use internationally recognized conversion factors, updated to current standards.
| Joules (J) | Watt-hours (Wh) |
|---|---|
| 1 J | 0.00027778 Wh |
| 10 J | 0.00277778 Wh |
| 50 J | 0.013889 Wh |
| 100 J | 0.027778 Wh |
| 250 J | 0.069444 Wh |
| 500 J | 0.138889 Wh |
| 1000 J | 0.277778 Wh |
| 2000 J | 0.555556 Wh |