Appliance electricity cost calculator
Pick an appliance, check the watts on its label, and see what it costs to run at your state's latest electricity price.
Portable space heater, 1,500 W, 8 h/day at 21.77¢ per kWh (Pennsylvania average, August 2026)
$78.37 / month
| Per hour of use | $0.327 |
| Per day | $2.61 |
| Per month (30 days) | $78.37 |
| Per year | $954 |
| Electricity per day | 12.00 kWh |
Same use in the cheapest state (Nevada, 12.72¢): $45.79/month · most expensive (Hawaii, 47.18¢): $169.85/month.
State averages are total revenue ÷ kWh sold, so fixed charges are spread over every kWh; your utility's price for extra kWh can be a little different (tiers, time-of-use). Heaters with a thermostat may run fewer hours than entered.
The formula
Watts × hours per day ÷ 1,000 = kWh per day. kWh × price per kWh = cost. A 1,500 W heater running 8 hours uses 12 kWh a day; at 20¢ per kWh that is $2.40 a day.
Where the wattages come from
Default wattages are typical nameplate values from Estimating Appliance and Home Electronic Energy Use (U.S. DOE, reprinted by Virginia Cooperative Extension, 2020). The label on your appliance is more accurate. Appliances with a thermostat or compressor (fridges, freezers, heaters) cycle on and off, so they use less than their nameplate wattage × hours.