Electricity Cost Calculator
Pick an appliance or enter its wattage, set how long it runs, and choose your state. We use the latest official average residential electricity price for every US state from the EIA (August 2026 data).
How the electricity cost is calculated
kWh per day = watts × hours per day ÷ 1,000
Cost per day = kWh per day × price per kWh
Cost per month = cost per day × days used
Electricity is billed in kilowatt-hours (kWh). One kWh is 1,000 watts used for one hour. A 1,500-watt space heater running for one hour uses 1.5 kWh.
Example: a space heater
A 1,500 W space heater used 6 hours a day uses 9 kWh per day. At the U.S. average of 18.16¢ per kWh that is about $1.63 a day, or about $49 a month. In a high-price state like California or Hawaii the same heater can cost almost twice as much.
Typical appliance wattage
| Appliance | Typical watts | Notes |
|---|---|---|
| Central AC | 2,000–5,000 | Runs in cycles; real use depends on weather and thermostat |
| Space heater | 750–1,500 | Most run at 1,500 W on high |
| Refrigerator | 100–250 (running) | The compressor cycles on and off; about 1–2 kWh/day |
| Electric water heater | 3,000–5,500 | Often the second-largest user in a home |
| Clothes dryer | 2,000–5,000 | About 2–5 kWh per load |
| TV (LED) | 50–150 | Larger screens use more |
| Level 2 EV charger | 7,200–11,500 | See our EV charging cost calculator |
Appliances with motors or compressors don't run at full power all the time. If you have a plug-in energy monitor, use its measured kWh for the most accurate result.
Want to compare states? See electricity rates by state.
Frequently asked questions
How much does it cost to run a 1,500 watt heater for an hour?
1,500 watts for one hour is 1.5 kWh. At the U.S. average residential price of 18.16¢ per kWh that is about $0.27 per hour.
How do I find my appliance's wattage?
Look for a label on the back or bottom, or in the manual. If it lists amps and volts instead, multiply them: watts = amps × volts (for example 10 A × 120 V = 1,200 W).
Why is my electric bill higher than the calculator?
Bills include fixed customer charges, delivery fees and taxes, and some utilities use tiered or time-of-use prices. The calculator shows the energy cost only.
Where does the state electricity price come from?
We use the average residential price by state from the U.S. Energy Information Administration (EIA), Electric Power Monthly, Table 5.6.A. The current data is for August 2026.
Does an appliance use power when it is turned off?
Many devices draw a small 'standby' load, often 1–5 watts. A smart power strip can cut this waste.
Sources
- U.S. Energy Information Administration — Average price of electricity by state (Electric Power Monthly, Table 5.6.A)
- U.S. Department of Energy — Estimating appliance and home electronic energy use