Calculators / Energy and insulation
What does it cost to run?
Put in the watts and how long it runs, or the kWh off a label or bill, and pick your state. You’ll get the cost per day, month and year.
Updated · How we check our numbers
At 18.19¢ a kWh
$33.18 a month
182 kWh a month at the US average, 18.19¢ a kWh. About $398 a year.
- Per day
- $1.09
- Per year
- $398
- Rate
- 18.19¢ / kWhEIA, year to date through August 2026
Estimate for planning only, not professional advice. Check the manufacturer’s instructions, your local code and a licensed professional before you buy, build or install. Use at your own risk. Terms.
1500 W × 4 h ÷ 1,000 = 6 kWh on the days it runs
7 days a week → 6 kWh a day on average
× 18.19¢ = $1.09 a day
What it costs
18.19¢ / kWh- Per hour of running1.5 kW × 18.19¢27¢
- Per day6 kWh$1.09
- Per month182 kWh$33.18
- Per year2,190 kWh$398
Energy charges only; fixed monthly fees and taxes aren’t included.
US homes averaged 18.19¢ a kWh (year to date through August 2026) (EIA). Your utility’s rate, time-of-use pricing and fixed monthly charges can differ a lot; the price per kWh on your bill is the one to use.
Fridges, heaters, hot tubs and AC switch on and off, so their nameplate watts overstate the hours they actually draw. If you know the kWh a day or a year (an EnergyGuide label, a plug-in meter), use that instead.
How we work it out
kWh = watts × hours ÷ 1,000 · cost = kWh × price per kWh
A 1,500 W space heater running 4 hours uses 6 kWh. At the US average of 18.19¢ a kWh, that's about $1.09 a day.
State prices are the U.S. Energy Information Administration's average residential price (year to date through August 2026, released October 23, 2026), from its Electric Power Monthly. They're averages across every utility in the state, so your own bill is more exact: use the price per kWh on it, adding supply and delivery if they're split.
Watts on a label are the most a thing draws. Anything with a thermostat, like a fridge, heater, hot tub or AC, cycles on and off, so it uses less than watts × hours. If you have its kWh a year (the yellow EnergyGuide label) or a reading from a plug-in meter, use that.
Prices for every state are in the electricity cost by state table.
Where the numbers come from
Reference
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