Electricity Cost Calculator
Work out what any appliance costs to run from its wattage, hours of use and your price per kWh — using the Ofgem price-cap rate of 26.35p per unit for 2025.
Appliance running cost
Watts × hours ÷ 1000 × price per kWh.
Based on the Ofgem electricity price cap (26.35p/kWh). Your tariff and region may differ — check your bill.
How to work out electricity running costs
The cost of running any electrical appliance comes down to three numbers: its power in watts, how many hours you use it, and your price per kilowatt-hour (kWh). The formula is simple: watts × hours ÷ 1,000 gives the kWh used, then multiply by your unit price. This calculator does it instantly and scales the answer to a day, week, month and year.
A 2,000W appliance used for 1 hour uses 2 kWh. At the 2025 Ofgem cap of 26.35p per kWh, that costs about 53p. Run it an hour a day and that's roughly £3.69 a week or £192 a year.
Typical appliance wattages
| Appliance | Typical power | Cost per hour* |
|---|---|---|
| Kettle | 3,000 W | ≈ 79p |
| Electric oven | 2,100 W | ≈ 55p |
| Washing machine | 700 W (cycle) | ≈ 18p |
| Fridge-freezer | 100 W avg | ≈ 3p |
| LED TV | 80 W | ≈ 2p |
*At 26.35p/kWh. Source: Ofgem — price cap unit rates, Oct–Dec 2025.
Why your unit price matters most
The biggest variable is your unit rate, which depends on your tariff, region and meter type. The Ofgem price cap sets a maximum average of 26.35p per kWh for default tariffs, but fixed deals and time-of-use tariffs (like Economy 7) can be cheaper or dearer. Update the price box above to match your own bill. To see your full bill including the daily standing charge, use our electricity and energy bill tools.
Frequently asked questions
How do I calculate the cost of running an appliance?
Multiply the appliance's power in watts by the hours you use it, divide by 1,000 to get kilowatt-hours, then multiply by your price per kWh. For example, 2,000W for 1 hour is 2 kWh; at 26.35p that is about 53p.
What is the cost of 1 kWh of electricity in the UK?
Under the Ofgem price cap for October to December 2025, the average price is 26.35p per kWh for default tariffs paid by Direct Debit, plus a daily standing charge of about 53.68p. Your exact rate depends on your tariff and region.
How much does it cost to boil a kettle?
A 3,000W kettle takes roughly 3 minutes to boil, using about 0.15 kWh. At 26.35p per kWh that's around 4p per boil. Boiling only the water you need is the easiest way to cut the cost.
Why is my electricity bill higher than this estimate?
This tool shows usage cost only. Your full bill also includes a daily standing charge (about 53.68p a day), VAT and any debt repayments. High-power heating and hot-water appliances also add up faster than people expect.
Is the 26.35p rate fixed?
No. It is the Ofgem price-cap average for default tariffs, reviewed every three months. Fixed-rate deals, prepayment meters and Economy 7 tariffs can differ, so enter your own unit price for an exact figure.