Electricity Cost Calculator
What any appliance costs to run, per hour, day, month and year, from its power in watts, how long it's on and your electricity price per kWh. Start from a common appliance or enter your own.
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How to work out what an appliance costs to run
- Pick a common appliance, or enter its power in watts or kilowatts.
- Enter how many hours a day and days a week it’s used.
- Enter your price per kWh to see the cost per hour, day, month and year.
How it's worked out
Energy used is power × time: a 3,000-watt (3 kW) kettle running for 15 minutes uses 3 × 0.25 = 0.75 kilowatt-hours (kWh), the unit your bill charges for. Multiply by the price per kWh for the cost. Find an appliance's wattage on its rating plate or in its manual. The figure there is the maximum: fridges, washing machines, dishwashers, heaters and computers draw far less on average because they cycle on and off, so the presets use typical average figures for those. A plug-in energy monitor gives the most accurate reading.
Your price per kWh (the unit rate) is on your bill or tariff; standing charges are a fixed daily fee that doesn't depend on use, so they're left out. Months are averaged as 365 ÷ 12 days. Everything is calculated in your browser.
Questions about electricity costs
How do I calculate the cost of running an appliance?
Kilowatts × hours × price per kWh. A 3 kW kettle used for 15 minutes a day uses 0.75 kWh; at 25p per kWh that’s about 19p a day.
Where do I find an appliance’s wattage?
On its rating plate or label, or in the manual. That’s the maximum; fridges, washing machines and heaters average less because they cycle on and off.
What is a kWh?
A kilowatt-hour: the energy a 1,000-watt appliance uses in an hour. It’s the unit on your electricity bill.
Does it include the standing charge?
No. The standing charge is a fixed daily fee you pay however much you use, so it doesn’t change what each appliance costs to run.