Appliance Running Cost Calculator
Enter an appliance's wattage and how long you use it to see exactly what it costs to run — per hour, day, month, and year. Pick a preset or type your own numbers.
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How to calculate an appliance's running cost
Every appliance has a power rating in watts. Convert that to kilowatts (divide by 1,000), multiply by the hours you run it, and multiply by your electricity price. That's it:
Cost = (watts ÷ 1000) × hours × price per kWh
Example: a 1,500-watt space heater run 5 hours a day at $0.16/kWh costs (1,500 ÷ 1,000) × 5 × $0.16 = $1.20 a day. Over a 30-day month that's $36 — and if it runs all winter, real money. This is why high-wattage heating devices (space heaters, dryers, water heaters) dominate bills, while low-wattage electronics barely register.
Typical appliance wattage
| Appliance | Watts | Cost/hr @ $0.16 |
|---|---|---|
| Space heater | 1,500 | ~24¢ |
| Window AC | 1,200 | ~19¢ |
| Clothes dryer | 3,000 | ~48¢ |
| Refrigerator (avg) | 150 | ~2.4¢ |
| LED TV | 90 | ~1.4¢ |
| Phone charger | 5 | ~0.08¢ |
Want the whole-home picture instead of one device? Use the Electricity Bill Calculator. Charging an EV? The EV Charging Cost Calculator handles that specifically.
Frequently asked questions
Where do I find an appliance's wattage?
Check the label or metal plate on the back or bottom, or the manual. If only amps and volts are listed, multiply them: watts = volts × amps (e.g. 120 V × 10 A = 1,200 W).
Why does my fridge use less than its label says?
Appliances with a thermostat or motor cycle on and off. A fridge might be rated 150–200 W but only runs about a third of the time, so its real average draw is lower. Use realistic daily hours for cycling appliances.
Does standby (phantom) power matter?
A little. Devices left plugged in draw a few watts on standby. Individually tiny, but across a whole home it can add a few dollars a month.