Energy cost calculator

How the energy cost calculator works

Every electrical appliance has a power rating in watts (W) or kilowatts (kW), usually printed on a label underneath or on the back. Your supplier charges you for each kilowatt-hour (kWh) you use, which is 1,000 watts running for one hour. So the running cost of any appliance comes down to one simple sum:

cost per hour = (watts ÷ 1,000) × unit rate in pence per kWh

The calculator multiplies that by the hours you use it each day and the days you use it each week, then scales up to a year (365 days). It shows pence for small amounts and pounds for larger ones.

The unit rate we use: October to December 2026 price cap

Unless you change it, the calculator uses 26.32p per kWh. That is Ofgem's average electricity unit rate for a household on a standard variable tariff paying by Direct Debit, for the price cap period running from 1 October to 31 December 2026. The standing charge is 54.83p a day. These are averages across England, Scotland and Wales, so your own rate depends on your region and how you pay.

The government has also removed VAT from household electricity between 1 October 2026 and 31 March 2027, and the 26.32p figure already reflects that. If you're on a fixed deal, use the unit rate printed on your bill or in your supplier's app instead.

How much does it cost to run common appliances?

These figures use the 26.32p rate and typical wattages. Real appliances vary, and anything with a thermostat (ovens, fridges, heaters on a low setting) switches on and off, so it uses less than its maximum rating over time.

A kettle looks expensive at 79p an hour, but you only boil it for a few minutes at a time. Boiling a full kettle for three minutes costs about 4p.

Worked example: a 2kW electric heater

A 2,000W fan heater uses 2 kWh every hour. At 26.32p per kWh that's 52.64p, or about 53p an hour. Run it for three hours every evening and it uses 6 kWh a day, costing £1.58 a day, £11.05 a week and £576.41 a year if you used it all year round. Over a five-month winter that's still roughly £240, which is why heating a single room with a plug-in heater can cost more than you'd expect.

Air fryer vs oven: which is cheaper?

An air fryer rated at 1,500W running for 30 minutes uses 0.75 kWh and costs about 20p. An electric oven averaging 2,000W over an hour, including preheating, costs about 53p. For small portions the air fryer is usually cheaper because it cooks faster and heats a much smaller space. For a full family roast, the oven can work out similar per portion.

Tips to cut appliance running costs

• Only boil what you need. Kettles use energy in proportion to how much water you heat.
• Wash at 30°C. Most of a washing machine's electricity goes on heating water, so a cooler wash uses noticeably less.
• Dry clothes outside or on an airer when you can. A vented tumble dryer is one of the most expensive appliances to run; heat pump dryers use around a third as much.
• Check your unit rate. If you're on an off-peak tariff such as Economy 7, run timed appliances overnight and enter your cheaper night rate here.
• Switch off at the wall. Games consoles and TVs on standby still draw a few watts around the clock.

Thinking about an electric car? Our EV charging cost calculator uses the same unit rates, and the fuel cost calculator works out petrol and diesel journeys. To compare a new price with an old one, try the percentage calculator.

Last reviewed October 2026 using 2026/27 figures. This calculator gives an estimate for guidance only.