100 Watts to Joules
Watts measure power and joules measure energy, so the answer depends on time. Here is what a 100 W device uses over each period.
100 J per second
Because 1 watt = 1 joule per second, 100 W delivers 100 J every second it runs.
- Per minute
- 6,000 J
- Per hour
- 360,000 J
- Per hour (kWh)
- 0.1 kWh
- Per day
- 8,640,000 J
100 watts to joules, explained
A watt is a rate: one watt means one joule of energy is used every second. So 100 watts means 100 joules per second. To get a total number of joules you multiply by how long the power runs.
For example, a 100 W device left on for one hour uses 100 × 3,600 = 360,000 J. Over a full day it uses 8,640,000 J. On an electricity bill, one hour of use is 0.1 kWh.
100 W draws about the same power as 1.7 old-style 60 W incandescent bulbs running at once. One hour at 100 W consumes 0.1 kWh of electricity — about $0.015 at a US average residential rate of $0.15 per kWh.
joules = 100 W × time in secondsPlayStation 5 (menu/idle) (100 W)
A PS5 gaming console draws roughly 100 watts of power when browsing menus or streaming movies.
Electrical Power Comparison Scale
Need a different power or time? Use the interactive converter below for any combination.
100 W energy over time
| Time on | Energy (joules) |
|---|---|
| 1 second | 100 J |
| 1 minute | 6,000 J |
| 10 minutes | 60,000 J |
| 1 hour | 360,000 J |
| 6 hours | 2,160,000 J |
| 1 day | 8,640,000 J |
Convert any wattage and time
The full Watts to Joules converter handles W, kW, MW, any time unit, and the reverse joules→watts and time calculations.
FAQ: 100 watts
How many joules is 100 watts?
100 watts is not a fixed number of joules on its own — watts measure power and joules measure energy, so you need a time. A 100 W device uses 100 J every second, 360,000 J over one hour (0.1 kWh).
How do you convert 100 watts to joules?
Multiply 100 by the number of seconds the power runs. Joules = 100 × time in seconds. For one hour that is 100 × 3,600 = 360,000 J.
How much energy does a 100 W device use per hour?
A 100 W device running for one hour uses 360,000 J, which is 0.1 kWh on an electricity bill.