Estimate only. Your bill's actual rate, time-of-use pricing and how the appliance cycles change the real cost.
How the cost is calculated
- Energy: watts ÷ 1,000 × hours per day × days per month gives kWh per month.
- Cost: kWh × your state's average residential electricity price (EIA, Table 5.6.B).
Where to find the watts
Look at the label on the back or bottom of the appliance, or in its manual. If it only shows amps, multiply amps × volts (120 V for most outlets in the U.S.) to get watts.
Why your real use can be lower
The label shows the maximum power. Appliances with a thermostat or compressor, such as refrigerators, freezers, air conditioners and water heaters, turn on and off, so their average use is lower than watts × hours. For those, the yellow EnergyGuide label, when available, shows an estimated yearly kWh.