How electricity costs are calculated
Energy use is power times time. A device drawing 150 watts for 8 hours uses 1.2 kilowatt-hours (kWh). Multiply by your price per kWh to get the cost.
The wattage is usually printed on the device's label. Devices that run in standby also use a little power, which this simple calculator does not include.
How to use the Electricity Cost Calculator
- 1Enter the device's power in watts.
- 2Enter how many hours per day it runs.
- 3Enter your price per kWh and read the costs.
Frequently asked questions
Where do I find the wattage?
On the device's rating plate or in its manual.
What price per kWh should I use?
Use the price from your electricity bill, in cents.