Electricity cost calculator
Work out the kilowatt hours and running cost of any appliance, per day, month and year.
About this calculator
Enter the appliance power in watts, how many hours a day it runs, and your price per kilowatt hour. You will see the energy used and the cost per day, month and year.
Look for the wattage on the appliance label. Add standby watts for devices that stay plugged in.
Measurements and terms explained
- Watt (W)
- The power an appliance draws. 1,000 W = 1 kilowatt (kW).
- Kilowatt hour (kWh)
- One kilowatt used for one hour, the unit your supplier bills.
- Standby power
- Electricity used while a device is off but still plugged in.
Common questions
How do I find my price per kWh?
It is on your electricity bill, often as a pence per kWh unit rate.
What uses the most electricity?
Heating, cooking and tumble dryers are usually the biggest, because they draw thousands of watts.
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