Electricity Cost Calculator
Enter any device's wattage and daily hours — or its energy per use — and get the real cost at your state's current rate (April 2026 data).
Per hour
1.9¢
Per day
7.5¢
Per month
$2.29
Per year
$27.45
Uses 12 kWh/month at 18.8¢ per kWh.
How the math works
Electricity is billed in kilowatt-hours (kWh) — one kilowatt-hour is 1,000 watts running for one hour. The formula behind this calculator:
watts ÷ 1,000 × hours per day × rate (¢/kWh) = daily cost
For appliances that work in discrete sessions (dishwashers, dryers, EV charges), it's simpler to count energy per use: kWh per use × uses per week, converted to a monthly figure. Not sure what a device draws? Browse our appliance database for measured typical values, or check what a kilowatt-hour actually is.
Frequently asked questions
How do I calculate the electricity cost of an appliance?
Multiply the appliance’s wattage by hours used per day, divide by 1,000 to get kilowatt-hours, then multiply by your electricity rate. Example: a 1,500 W heater × 8 hours = 12 kWh; at 17¢/kWh that’s about $2.04 per day. This calculator does exactly that with your state’s current rate.
Where do I find an appliance’s wattage?
Check the label on the back or bottom of the device, the power brick, or the manual. Labels state maximum draw — actual use is often lower. Our appliance pages list realistic typical wattages for over 140 devices, or a $10 smart plug with energy monitoring will measure the real number.
What electricity rate should I use?
The state averages built into this calculator are current EIA figures and work well for estimates. For precision, divide the total charges on your last bill by the kWh used — that captures delivery fees and taxes your nominal rate leaves out.
Why is my bill higher than the appliance math suggests?
Bills include fixed charges, delivery fees, and taxes on top of usage. Always-on devices (water heaters, fridges, standby electronics) also run more hours than people assume. Try the whole-home bill analyzer on our homepage to see the full picture.