Saving EnergyHow Much Does It Cost to Run an Air Conditioner? (Window and Central AC)
Estimate the cost to run a window or central air conditioner using published wattages and the DOE formula: watts × hours ÷ 1,000 × your rate.
Appliance energy cost calculator
Enter an appliance's wattage and how long you use it to see the cost per hour, day, month and year at your state's rate.
State rates are 12-month residential averages from EIA, through August 2026. Use the rate on your own bill for the most accurate result.
How to use the appliance energy cost calculator
- Find the wattage on the appliance label, manual or the table below.
- Enter how many hours a day it runs and how many days a month.
- Choose your state (or type your own rate).
- Read the cost per day, month and year.
Formula
kWh per day = watts × hours ÷ 1,000; cost = kWh × rate. This is the method the US Department of Energy recommends. Appliances with a thermostat or compressor (fridges, heaters, AC) run at full power only part of the time, so real costs are usually lower.
Worked examples
| Appliance | Typical wattage | Cost per hour (US avg) |
|---|---|---|
| Space heater | 750–1,500 W | $0.14–$0.27 |
| Refrigerator | 725 W | $0.13 |
| Clothes dryer | 1,800–5,000 W | $0.33–$0.91 |
| Washing machine | 350–500 W | $0.06–$0.09 |
| Dishwasher | 1,200–2,400 W | $0.22–$0.44 |
| Electric water heater | 4,500–5,500 W | $0.82–$1.00 |
| Microwave | 750–1,100 W | $0.14–$0.20 |
| Window fan | 55–250 W | $0.01–$0.05 |
| Ceiling fan | 65–175 W | $0.01–$0.03 |
| Furnace fan | 750 W | $0.14 |
| Dehumidifier | 785 W | $0.14 |
| Coffee maker | 900–1,200 W | $0.16–$0.22 |
| Electric kettle | 1,500 W | $0.27 |
| Toaster | 800–1,400 W | $0.15–$0.25 |
Rates by state
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
What common appliances cost to run
- Space heater (750–1,500 W)
- Refrigerator (725 W)
- Clothes dryer (1,800–5,000 W)
- Washing machine (350–500 W)
- Dishwasher (1,200–2,400 W)
- Electric water heater (4,500–5,500 W)
- Microwave (750–1,100 W)
- Window fan (55–250 W)
- Ceiling fan (65–175 W)
- Furnace fan (750 W)
- Dehumidifier (785 W)
- Coffee maker (900–1,200 W)
- Electric kettle (1,500 W)
- Toaster (800–1,400 W)
- Toaster oven (1,225 W)
- Hair dryer (1,200–1,875 W)
- Clothes iron (1,000–1,800 W)
- Vacuum cleaner (1,000–1,440 W)
- Desktop computer (120 W)
- Laptop (50 W)
- Television (flat screen) (120 W)
- Electric blanket (60–100 W)
- Well pump (250–1,100 W)
- Aquarium (50–1,210 W)
Frequently asked questions
How do I calculate how much electricity an appliance uses?
Multiply its wattage by the hours you use it, then divide by 1,000 to get kWh. Multiply kWh by your rate for the cost.
How much does it cost to run 1,000 watts for an hour?
1,000 watts for one hour is 1 kWh, which costs about 18.16¢ at the US average rate.
Where do I find an appliance's wattage?
Check the label on the back or bottom, the manual, or the EnergyGuide label. A plug-in electricity meter gives the most accurate reading.
Related guides
Saving Energy
Saving EnergyPhantom (Standby) Power: What It Costs and How to Cut It
Standby or phantom power can make up 5–10% of home energy use, per DOE. Learn how to measure it, calculate its cost and cut it.
Saving EnergyHow to Lower Your Electric Bill: 12 Practical, Sourced Ways
Practical ways to lower your electric bill, from free thermostat and standby-power fixes to LEDs, insulation and rate plans, each backed by DOE, EPA or EIA guidance.
More calculators
- Electricity cost calculatorTurn kWh into dollars at your state's rate.
- Electric bill calculatorEstimate a monthly bill from your usage.
- kWh calculatorConvert watts and hours into kWh – and cost.
- Watts to amps calculatorConvert watts ↔ amps at 120 V, 240 V or any voltage.
- Solar panel calculatorSystem size, cost, savings and payback.
- EV charging cost calculatorHome charging cost per month and per mile.