Convert Joule to Watt Hour
Use this free converter to change joules (J) into watt hours (Wh). Joule and watt hour both measure energy. As a quick reference, 1 J equals 0.00027777778 Wh, and 1 Wh equals 3600 J.
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Watt Hour (Wh)
0.00027777778
1 J = 0.00027777778 Wh
Energy conversion table
| Joule | Watt Hour |
|---|---|
| 0.01 | 0.0000027777778 |
| 0.1 | 0.000027777778 |
| 0.5 | 0.00013888889 |
| 1 | 0.00027777778 |
| 2 | 0.00055555556 |
| 3 | 0.00083333333 |
| 5 | 0.0013888889 |
| 10 | 0.0027777778 |
| 20 | 0.0055555556 |
| 25 | 0.0069444444 |
| 50 | 0.013888889 |
| 100 | 0.027777778 |
| 1,000 | 0.27777778 |
How to convert Joule to Watt Hour
Multiply the joule value by 0.00027777778 to get watt hours.
- Enter the number of joules you want to convert.
- The converter instantly shows the equivalent value in watt hours.
- Worked example: 15 J × 0.00027777778 = 0.0041666667 Wh.
- Use the swap button to reverse the conversion (watt hour to joule).
About these units
Joule (J)
- Definition
- The joule (J) is the SI unit of energy, the work done by a force of one newton over one meter.
- History
- Named after physicist James Prescott Joule, who studied the link between heat and work.
- Current use
- Joules measure energy, work, and heat throughout science and engineering.
Watt Hour (Wh)
- Definition
- A watt-hour (Wh) is the energy of one watt sustained for one hour, equal to 3,600 joules.
- History
- It arose with the electricity industry as a practical billing unit.
- Current use
- Watt-hours rate batteries and small energy stores.
Frequently asked questions
How many watt hours are in a joule?
There are 0.00027777778 Wh in 1 J. To convert, multiply the number of joules by 0.00027777778.
How do I convert joules to watt hours?
Multiply the joule value by 0.00027777778 to get watt hours. For example, 10 J = 0.0027777778 Wh.
Is this joule-to-watt hour converter free?
Yes. This converter is completely free, runs entirely in your browser, and requires no sign-up. Your inputs never leave your device.
Convert Joule to other energy units
| Unit | 1 Joule equals |
|---|---|
| Kilojoule (kJ) | 0.001 kJ |
| Calorie (cal) | 0.23900574 cal |
| Kilocalorie (kcal) | 0.00023900574 kcal |
| Watt Hour (Wh) | 0.00027777778 Wh |
| Kilowatt Hour (kWh) | 2.7778e-7 kWh |
| Electronvolt (eV) | 6.2415e+18 eV |
| British Thermal Unit (BTU) | 0.00094781712 BTU |
| Foot-Pound (ft·lb) | 0.73756215 ft·lb |