How it works
An appliance's running cost is the energy it uses (watts × hours, converted to kilowatt-hours) multiplied by the price you pay per kWh. We add up every appliance you list, scale for how many days a week you use each one, and show the cost per day, month and year.
Appliances that cycle on and off, such as fridges and freezers, use much less than their label wattage suggests. For those we use an average draw across the day; the most accurate figure is the yearly kWh on the energy label.
The formula
kWh per day = watts × hours per day × how many ÷ 1,000 × (days per week ÷ 7) cost per day = kWh per day × price per kWh cost per month = cost per day × 30.42 (365 ÷ 12) cost per year = cost per day × 365
Worked example
A fridge, a TV for 4 hours and a 1,500 W space heater for 4 hours a day, at the US average of 18.2¢ per kWh.
| Appliance | Working | kWh a day |
|---|---|---|
| Refrigerator (average draw) | 60 W × 24 h ÷ 1,000 | 1.44 |
| TV (55-inch LED) | 80 W × 4 h ÷ 1,000 | 0.32 |
| Space heater (high) | 1,500 W × 4 h ÷ 1,000 | 6.00 |
| Total | 7.76 kWh × $0.182 | $1.41 a day |
| Per month | $1.4123 × 30.42 | $42.96 |
| Per year | $1.4123 × 365 | $515.50 |
The space heater is 77% of the cost: high-wattage heating appliances dominate most bills.
Frequently asked questions
How do I calculate the cost of running an appliance?
Multiply the watts by the hours it runs and divide by 1,000 to get kWh, then multiply by your price per kWh. A 1,000 W appliance running for 2 hours uses 2 kWh; at 18.2¢ that costs $0.36.
How much does it cost to run a refrigerator?
A typical modern fridge uses about 1.44 kWh a day, so at the US average of 18.2¢ it costs about $0.26 a day, $7.97 a month or $96 a year. Older fridges can use twice as much.
How do I find an appliance's wattage?
Look for a label on the back or underside, or in the manual. If it only lists amps, multiply amps by your voltage (120 V in the US and Canada, 230 V in the UK and Australia). A plug-in energy meter measures real use most accurately.
Why doesn't the result match my electric bill?
Bills also include fixed daily or monthly charges, taxes, and sometimes tiered or time-of-use prices. Appliances you did not list, such as heating, water heating and devices on standby, add up too.
What uses the most electricity in a home?
Usually heating and cooling, followed by water heating, then large appliances such as dryers, ovens and fridges. Anything that makes heat with electricity and runs for hours will dominate the bill.
Sources
- Default prices: US average residential price, EIA 2026 forecast (checked Oct 2026); Ofgem price cap unit rate, 1 Oct – 31 Dec 2026, Direct Debit (VAT on electricity is 0% until 31 Mar 2027).
- US Department of Energy, estimating appliance and home electronic energy use.
Related guides
Estimates are for planning only and are not financial advice. Get written quotes before you buy.