The watt-hour
The watt-hour (Wh) equals 3,600 joules — the energy delivered by one watt of power over one hour. It is the natural unit for batteries, small electronics, and short-duration electrical loads.
Watt-hours to Joules Converter
1 Wh = 3600 J
1 watt-hour equals 3600 joules. To convert watt-hours to joules, multiply the watt-hour value by 3600. For quick reference: 1 Wh = 3600 J, 5 Wh = 18000 J, 10 Wh = 36000 J, 100 Wh = 360000 J.
Formula
Joules = Watt-hours × 3600Quick
How to convert watt-hours to joules
Take your value
Start with your value in watt-hours.
Multiply by 3600
Multiply the watt-hour value by 3600. This is the exact conversion factor from watt-hours to joules.
Read the result
The product is your value in joules. For example, 5 Wh × 3600 = 18000 J.
Conversion formula
The exact factor from watt-hours to joules is 3600.
Joules = Watt-hours × 3600
Watt-hours to Joules conversion table
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Watt-hours (Wh) | Joules (J) |
|---|---|
| 0.001 Wh | 3.6 J |
| 0.01 Wh | 36 J |
| 0.1 Wh | 360 J |
| 0.5 Wh | 1800 J |
| 1 Wh | 3600 J |
| 1.5 Wh | 5400 J |
| 2 Wh | 7200 J |
| 5 Wh | 18000 J |
| 10 Wh | 36000 J |
| 20 Wh | 72000 J |
| 50 Wh | 180000 J |
| 100 Wh | 360000 J |
| 200 Wh | 720000 J |
| 250 Wh | 900000 J |
| 500 Wh | 1800000 J |
| 1000 Wh | 3600000 J |
| 2000 Wh | 7200000 J |
| 2500 Wh | 9000000 J |
| 3600 Wh | 12960000 J |
| 5000 Wh | 18000000 J |
| 7500 Wh | 27000000 J |
| 10000 Wh | 36000000 J |
| 25000 Wh | 90000000 J |
| 50000 Wh | 180000000 J |
| 100000 Wh | 360000000 J |
| 250000 Wh | 900000000 J |
| 500000 Wh | 1800000000 J |
| 1000000 Wh | 3600000000 J |
| 2000000 Wh | 7200000000 J |
| 3600000 Wh | 12960000000 J |
| 5000000 Wh | 18000000000 J |
| 10000000 Wh | 36000000000 J |
| 25000000 Wh | 90000000000 J |
| 50000000 Wh | 180000000000 J |
| 100000000 Wh | 360000000000 J |
| 250000000 Wh | 900000000000 J |
| 500000000 Wh | 1800000000000 J |
| 1000000000 Wh | 3600000000000 J |
| 2000000000 Wh | 7200000000000 J |
| 5000000000 Wh | 18000000000000 J |
| 10000000000 Wh | 36000000000000 J |
| 20000000000 Wh | 72000000000000 J |
| 50000000000 Wh | 180000000000000 J |
| 100000000000 Wh | 360000000000000 J |
| 1000000000000 Wh | 3.6000 × 10^15 J |
| 10000000000000 Wh | 3.6000 × 10^16 J |
| 100000000000000 Wh | 3.6000 × 10^17 J |
| 1000000000000000 Wh | 3.6000 × 10^18 J |
| 10000000000000000 Wh | 3.6000 × 10^19 J |
| 100000000000000000 Wh | 3.6000 × 10^20 J |
Real-world reference
A typical smartphone battery stores about 15 Wh. An LED bulb uses 8 Wh per hour of operation. In joules, that gives you: 1 Wh = 3600 J, 10 Wh = 36000 J, 100 Wh = 360000 J.
Frequently asked questions
- How many joules are in 1 watt-hour?
- 1 watt-hour equals 3600 joules.
- How do I convert watt-hours to joules?
- Multiply the watt-hour value by 3600. So x Wh × 3600 = the equivalent in J.
- What is 5 watt-hours in joules?
- 5 watt-hours equals 18000 joules.
- What is 10 watt-hours in joules?
- 10 watt-hours equals 36000 joules.
- What is 100 watt-hours in joules?
- 100 watt-hours equals 360000 joules.
- How do I convert back from joules to watt-hours?
- Multiply the joule value by 0.000277778. For example, 1 J = 0.000277778 Wh.
- Is the watt-hour bigger than the joule?
- Yes. 1 watt-hour is larger than 1 joule — specifically 3600 times larger.
- Are these conversion factors exact?
- Yes. The factor of 3600 is derived directly from the SI definitions of watt-hour and joule.
About the watt-hour and the joule
The joule
The joule (J) is the SI derived unit of energy, work, and heat — defined as the energy transferred when a force of one newton acts over one meter. The joule is the standard unit in physics, chemistry, and most modern engineering documentation.