Electricity cost calculator
Start with a common appliance or enter any wattage. The result updates as you type and stays on your device.
This setup uses about 240 kWh in a 30-day month.
Please enter valid values within the ranges shown.
Default rate: U.S. residential average for April 2026, retrieved July 16, 2026. Replace it with the price on your bill for a closer estimate.
How the calculator works
Electric bills charge for energy, not just power. Converting watts to kilowatts connects the appliance label to the rate on your bill.
- Use active runtime, not simply 24 hours.
- Enter cents per kWh exactly as shown on the bill.
- For cycling appliances, enter active runtime or use a meter.
Use numbers from your home
- 01Find the input watts
Use the appliance label or manufacturer specification. For a compatible plug-in appliance, a power meter rated for its voltage, current, and load type can show a better average. Use circuit-level monitoring or professional help for hardwired and high-power equipment.
- 02Estimate active hours
A refrigerator is plugged in all day but its compressor cycles. Count operating time, not connection time.
- 03Use your effective rate
Divide usage-based charges by billed kWh if your plan includes tiers or time-of-use pricing.