Electricity cost calculator
Work out what any appliance costs to run per hour, day, month and year, using your state's current residential electricity rate.
Most portable electric heaters draw 1,500 W on high. (US DOE, small space heaters)
Start by picking an appliance from the list. The wattage and typical daily hours fill in automatically, using figures sourced from the US Department of Energy and ENERGY STAR. You can adjust either number to match your actual usage.
The state dropdown sets your electricity rate to the most recent EIA average for that state. If your bill shows a different rate, type it directly into the custom rate field. Rates vary by season, utility, and tariff structure, so your own bill is always the most accurate source.
Appliances like refrigerators and air conditioners do not draw full power continuously. They cycle on and off based on temperature. The presets here account for that with a duty cycle, so the cost shown reflects realistic average draw rather than peak wattage.
The annual figure assumes the same daily usage every day of the year. For seasonal appliances, multiply the per-day cost by the actual number of days you use it to get a more accurate seasonal total.
Cost = watts / 1000 x hours x duty cycle x your rate. Rates are EIA average residential prices for period 2026-03; appliance wattages and duty cycles are typical values from the US Department of Energy and ENERGY STAR, listed per preset.
Full formulas and data sources are on the methodology page.
Frequently asked questions
- How do I calculate the cost of running an appliance?
- Multiply the appliance's wattage by the hours it runs, divide by 1,000 to get kilowatt-hours, then multiply by your electricity rate. This calculator does that for you using your state's current average residential rate.
- Where does the electricity rate come from?
- State rates are average residential retail prices from the US Energy Information Administration, period 2026-03. You can also type in the exact rate from your own bill.
- Why does my fridge cost less than its wattage suggests?
- Appliances with compressors or thermostats cycle on and off, so they do not draw full power all the time. The presets here include a typical duty cycle for appliances that cycle.