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Electricity Cost Calculator: Cost to Run Any Appliance

Enter an appliance's wattage, how long it runs and your price per kilowatt-hour to see what it costs per hour, day, month and year. Presets cover space heaters, AC units, dryers, kettles and EV chargers, and it works with US, UK and European rates.

By Suman Sharma · Updated

Electricity cost · per applianceLocal

Typical wattage. Check the label on yours for an exact figure.

W
h
d
$/ kWh

Your bill lists it in cents per kWh: 17¢ is 0.17.

Cost per month
$46.54
$558.45 a year · 3,285 kWh
Per hour
$0.26
1.50 kWh
Per day
$1.53
9.0 kWh
Power
1,500 W

How to use this tool

  1. Choose the appliance or enter its power

    Pick a preset or type the wattage from the label. If the label only lists amps, switch to amps × volts.

  2. Set how long it runs

    Enter hours a day and days a week. For things that cycle on and off, like a fridge or AC, use the hours it's actually running.

  3. Enter your electricity price

    Choose $, € or £ and type the price per kWh from your bill. The monthly and yearly cost update straight away.

Example

A 1,500 W space heater, 6 hours a day, every day.

Input

  • Power: 1,500 W
  • Use: 6 hours a day, 7 days a week
  • Price: $0.17 per kWh

Result

  • Energy: 9 kWh a day, 3,285 kWh a year
  • Per day: $1.53
  • Per month: $46.54
  • Per year: $558.45
  • The same heater at a UK rate of £0.25: £68.44 a month

Most space heaters cycle once a room is warm, so the real figure is usually lower. Treat this as the worst case.

The formula

Your bill charges for energy in kilowatt-hours (kWh). One kWh is 1,000 watts running for one hour. So the cost of running an appliance is:

watts ÷ 1,000 × hours × price per kWh

A 1,500 W space heater uses 1.5 kWh every hour. At $0.17 per kWh that's about 25.5¢ an hour, whether you're in a studio apartment or a large house.

Where to find the numbers

  • Wattage: on the label or rating plate, usually on the back or underside, or in the manual. Look for W or kW.
  • Amps only: multiply amps by your voltage. That's about 120 V in the US and Canada, and 230 V in the UK and most of Europe.
  • Price per kWh: on your bill. US bills show cents per kWh; UK bills call it the unit rate; in Germany it's the Arbeitspreis. Use the energy price, not the daily standing or service charge.

Why real costs are often lower than the label suggests

The label shows maximum power. Appliances with a thermostat, like space heaters, AC units, fridges and dehumidifiers, switch on and off to hold a temperature, so over an hour they may run only part of the time. Use the hours the appliance actually draws power, or a plug-in energy meter for an exact reading. Devices like TVs and PCs also draw less than their rated maximum most of the time.

Typical wattage of common appliances

Ranges from US Department of Energy guidance and typical product labels. Check your own appliance's label for the best estimate.

  • LED bulb: 8 to 12 W
  • Laptop: 30 to 70 W
  • Desktop PC (gaming): 300 to 600 W under load
  • TV (55-inch LED): 50 to 150 W
  • Refrigerator: about 100 to 250 W while running; 1 to 2 kWh a day
  • Ceiling fan: 15 to 90 W
  • Window air conditioner: 500 to 1,500 W
  • Space heater: 750 to 1,500 W
  • Microwave: 600 to 1,200 W
  • Electric kettle: 1,500 to 3,000 W
  • Clothes dryer: 2,000 to 5,000 W
  • EV charger (Level 2): 7,000 to 11,500 W

From per-hour to monthly cost

Multiply the hourly cost by hours per day and then by 30 for a month. A 100 W device left on all day uses 2.4 kWh a day, about 72 kWh a month; at $0.17 per kWh that's about $12.24 a month or $147 a year. Always-on devices add up even when their wattage looks small.

Common errors

  • Typing the rate in cents

    17¢ per kWh is 0.17, not 17. Entering 17 makes everything 100 times too expensive.

  • Using kW as watts

    A 2.2 kW kettle is 2,200 W. Typing 2.2 in the watts box makes it look almost free to run.

  • Including the standing charge

    Your bill's daily standing or customer charge is paid whether the appliance is on or not, so leave it out of the per-kWh price.

  • Counting a fridge or AC as running all day

    Thermostat appliances cycle on and off. Twenty-four hours at full power overstates the cost a lot. Use a plug-in meter or the yearly kWh on the energy label instead.

Frequently asked questions

How much does it cost to run a space heater?

A typical 1,500 W heater uses 1.5 kWh an hour, so multiply 1.5 by your price per kWh. At $0.17 that's about 25.5¢ an hour, or $1.53 for 6 hours.

How do I calculate kWh from watts?

Divide watts by 1,000 and multiply by the hours it runs. A 400 W gaming PC used for 5 hours uses 2 kWh.

How do I convert amps to watts?

Multiply amps by volts. A 12.5 A appliance on a 120 V US outlet draws 1,500 W; a 10 A appliance on 230 V in Europe or the UK draws 2,300 W.

Does turning an appliance off at the wall save money?

Only the standby power, which for most modern devices is a watt or two. That's a few dollars a year at most per device, so focus on the high-wattage appliances first.

How much does it cost to run an air conditioner?

A 1,000 W window unit running 8 hours uses 8 kWh. At $0.17 per kWh that's $1.36 a day, or about $41 a month. Because the compressor cycles on and off, real use is often lower.

What uses the most electricity in a home?

Heating and cooling are usually the biggest, followed by water heating, clothes dryers and, if you have one, an electric car. Lights and electronics are smaller individually but run for many hours.

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