Electricity Cost Calculator
The running cost of an appliance is its energy use in kilowatt-hours multiplied by your price per kWh. This calculator works out how much any device costs to run — enter its power in watts, how long you use it and your electricity price to see the cost per day, month and year.
Electricity Cost Calculator
How appliance running costs work
Electricity is billed by the kilowatt-hour (kWh). To find a cost, convert the appliance power to kilowatts (divide watts by 1000), multiply by the hours of use to get kWh, then multiply by your price per kWh. The calculator scales that to a day, a month and a year.
Example
A 100 W light bulb used 5 hours a day uses 0.5 kWh per day. At a price of 0.20 per kWh that is 0.10 per day, about 3 per month and 36.50 per year.
Frequently asked questions
How do I calculate the cost of running an appliance?
Multiply the power in kilowatts (watts ÷ 1000) by the hours used to get kilowatt-hours, then multiply by your price per kWh. A 2000 W heater for 3 hours uses 6 kWh.
What is a kilowatt-hour (kWh)?
A kilowatt-hour is the energy used by a 1000-watt appliance running for one hour. It is the unit your electricity bill charges you by.
Where do I find an appliance power rating?
The wattage is usually printed on a label on the appliance or in its manual, given in watts (W) or sometimes amps and volts you can multiply.
How can I cut my electricity costs?
Use appliances for less time, switch to lower-wattage or efficient models, and avoid leaving devices on standby, which still draws power.
Does standby power cost money?
Yes. Many devices keep drawing a few watts on standby, which adds up over a year, so switching them off fully saves money.