How much does it cost to run an appliance?

The formula: watts, hours and your rate

The cost of running any appliance is its power in kilowatts, times the hours it runs, times what you pay per kilowatt-hour.

A kilowatt-hour (kWh) is 1,000 watts used for one hour. It’s the unit your utility bills you in, so the whole job is turning an appliance’s watts into kWh and then into dollars.

You need three numbers:

• Watts. Look on the label on the back or bottom of the appliance, or in the manual. If the label only lists amps, multiply amps by volts: most US appliances run on 120 volts, while big ones like clothes dryers and electric cooktops use 240 volts.
• Hours. How long it actually runs per day, week or month.
• Your price per kWh. It’s on your electric bill (more on that below). If you don’t have a bill handy, use the US average: $0.18 per kWh for homes in August 2026, from the US Energy Information Administration (EIA).

Worked example: how much electricity does a TV use?

A typical 55-inch LED TV uses about 100 watts while it’s on, which costs about 9 cents for 5 hours of viewing at $0.18 per kWh.

That 100-watt figure comes from ENERGY STAR’s list of certified TVs: 55-inch models draw 64 to 124 watts in normal use, and the middle of the list sits at about 95 watts. Bigger screens use more.

Now run the formula for a 100-watt TV that’s on 5 hours a day:

1. 100 watts × 5 hours = 500 watt-hours a day.
2. 500 ÷ 1,000 = 0.5 kWh a day.
3. 0.5 kWh × $0.18 = $0.09 a day.

So a modern TV is one of the cheaper things in your living room to run. Even a 65-inch set at the top of the range costs under $50 a year at this rate and this much viewing.

What common appliances cost to run

Most household appliances cost between 1 cent and 90 cents per hour of use at $0.18 per kWh, and the ones that make heat cost the most.

The wattages below are typical nameplate ranges from a Virginia Cooperative Extension energy fact sheet (the TV row is from ENERGY STAR). Nameplate wattage is roughly the most an appliance draws in steady use, so treat the hourly cost as the high end.

Two things stand out. First, short bursts of high power are cheap: a 10-minute blow-dry at 1,875 watts costs about 6 cents. Second, the dishwasher’s range is wide because its drying feature greatly increases its energy use, so air-drying the dishes is an easy saving.

The refrigerator is listed by the year, not by the hour, because it switches on and off all day. That’s true of any appliance with a thermostat, covered below.

How to find your electricity rate on your bill

Your real rate is the sum of all the per-kWh charges on your bill, and the fastest way to get it is to divide those charges by the kWh you used that month.

Most bills split the price into two parts: supply (or generation), for the electricity itself, and delivery (or distribution), for getting it to your house. Both are charged per kWh, so both belong in your rate. A flat monthly customer charge does not, because you pay it no matter how much you use.

It’s worth the minute it takes, because rates vary a lot by state. The $0.18 US average is EIA’s figure for residential customers in August 2026; that same month, state averages ran from about 13 cents in Nevada and Louisiana to more than 47 cents in Hawaii. In Hawaii, the same TV costs about 2.6 times as much to run.

If your bill shows different prices for different times of day, you’re on a time-of-use plan. Use the price for the hours when you actually run the appliance.

Standby power: what devices use when they’re “off”

Standby power, also called phantom load, is the electricity a device draws when it’s switched off or idle, and across a typical US home it adds up to 5-10% of electricity use, according to Lawrence Berkeley National Laboratory.

Any one device draws very little. Berkeley Lab says most products use less than 0.5 watts in standby, and every ENERGY STAR-certified TV on the current list uses 1 watt or less. A TV left in standby all year costs less than $1.60.

The problem is the number of devices: chargers, game consoles, cable boxes, smart speakers, microwaves with clocks, printers. For a home using EIA’s average of about 10,500 kWh a year, 5-10% is roughly 525 to 1,050 kWh, or about $95 to $190 a year at $0.18 per kWh.

You don’t need to unplug everything. Put the devices that sit together, like a TV, game console and soundbar, on a power strip, and switch the strip off when you’re done. That cuts standby power to all of them at once.

When the estimate is off: fridges, AC and space heaters

The formula overestimates anything controlled by a thermostat, because refrigerators, air conditioners and space heaters cycle on and off instead of running at full power around the clock.

The refrigerator is the classic trap. The Virginia Cooperative Extension fact sheet lists 725 watts for a frost-free 16-cubic-foot fridge. Multiply that by every hour of the year and you get 6,351 kWh, or more than $1,100. The fact sheet’s rule of thumb is to divide the plugged-in time by three, which gives about $380. A new full-size ENERGY STAR fridge is rated at about 300 to 700 kWh a year, which is $54 to $126. The two numbers differ because the fact sheet’s 725 watts is a label wattage, while ENERGY STAR’s figure is a yearly kWh estimate for current models.

So for these appliances, use better numbers than the label wattage:

• Refrigerators and freezers: use the estimated yearly kWh on the yellow EnergyGuide label, or look up your model in ENERGY STAR’s list, then multiply by your rate.
• Space heaters and window air conditioners: treat full power as the worst case. A 1,500-watt heater costs at most 27 cents an hour at $0.18 per kWh; when the thermostat lets it rest, it costs less.
• Anything you really want to pin down: a plug-in electricity usage monitor sits between the outlet and the appliance and shows the actual kWh over a few days. It fits standard 120-volt outlets only, so it can’t measure a 240-volt dryer or central AC.

Try it with your own numbers

The calculator below does the math for you: enter the watts, the hours per day and your rate, and it shows the cost per month and per year.

It starts with the TV example (100 watts, 5 hours, $0.18 per kWh). Swap in your appliance’s wattage and the rate from your bill.