Appliance energy cost calculator
Ever wondered what that heater, dryer or old fridge actually costs you? Enter the wattage, how often it runs and your own electricity rate to estimate the running cost per month and per year.
Where to find your kWh rate
Electricity is billed by the kilowatt-hour (kWh) — the energy used by a 1,000-watt appliance running for one hour. Your bill shows a "unit rate" or "price per kWh", and that single number is what turns energy use into money. It varies a lot by country, provider and tariff, which is exactly why this calculator asks you to enter your own rate instead of guessing one for you. If you're on a time-of-use tariff with different day and night prices, use the rate that applies when the appliance actually runs.
Finding an appliance's wattage is just as straightforward: check the rating label on the back or base, or the manual. Labels usually list power in watts (W) or kilowatts (kW); if it only shows kW, multiply by 1,000. For appliances that cycle on and off — fridges, washing machines — a cheap plug-in energy monitor gives a far more realistic figure than the nameplate rating.
Why some appliances cost more than others
The pattern is simple once you know it: anything that makes heat or cold is expensive to run. Kettles, ovens, electric heaters, hair dryers, tumble dryers and air conditioners all draw a lot of watts, so even short use adds up. Appliances that run around the clock, like fridges and freezers, rack up cost through sheer hours even at modest wattage. By contrast, LED bulbs, laptops, phone chargers and most electronics sip power and cost very little over a full year.
Standby still costs you. Many devices keep drawing a few watts even when "off". Individually it's small, but across a whole home it can quietly add up to a real chunk of the bill every year — add a standby figure above to see it.
How to cut the cost
Once you can see which appliance is driving the cost, the fixes follow naturally. Run heat-heavy appliances less or smarter, switch off standby drains, and replace the worst offenders with efficient models when they're due for renewal.
- Use full loads and eco settings on washers and dishwashers.
- Air-dry laundry instead of running the tumble dryer.
- Switch off devices at the wall to kill standby draw.
- Boil only the water you need in the kettle.
- Replace ageing, power-hungry appliances with efficient ones when they wear out.
Related guides & tools
Energy cost FAQ
Where do I find my electricity price per kWh?
Look on your latest electricity bill for the unit rate, usually shown as a price per kWh (kilowatt-hour). If you have more than one rate, such as a day and night tariff, use the rate that applies when the appliance actually runs. Entering your own rate makes the result match your real bill.
How do I find an appliance's wattage?
Check the rating label, usually on the back or base of the appliance, or in the manual. It will list power in watts (W) or kilowatts (kW). If only kW is shown, multiply by 1000 to get watts. A cheap plug-in energy monitor gives the most accurate real-world figure.
Why do some appliances cost so much more to run?
Anything that heats or cools is power-hungry: kettles, ovens, electric heaters, tumble dryers and air conditioners draw a lot of watts. Devices that run constantly, like fridges, also add up despite lower wattage. Low-power gadgets such as LED bulbs and laptops cost very little even over a full year.
Is this calculator accurate?
It's a rough estimate based on the figures you enter. Real appliances cycle on and off, vary their power draw and depend on settings, so actual costs differ. Because you enter your own electricity rate, the maths is correct for your tariff, but treat the total as guidance rather than a meter reading.
Find the energy hogs
Run the numbers on your biggest appliances, then tackle the worst offenders first. Small changes add up across a year.