How to Calculate Your Home Electricity Cost

Calculating electricity cost is straightforward when you know an appliance’s power, operating time, and electricity rate.

The basic formula is: cost = watts ÷ 1,000 × hours × electricity rate.

For example, a 1,000-watt appliance running 3 hours uses 3 kWh. At $0.16 per kWh, the cost is $0.48. For 30 days, the same daily schedule would use 90 kWh and cost about $14.40 under the same rate.

Use the correct electricity rate from your bill. Some bills contain fixed charges, taxes, fees, or tiered pricing, so multiplying total kWh by a simple rate may not reproduce the full bill.

For devices that cycle on and off, rated wattage is only an approximation of average consumption. Measured electricity use can be more accurate.

The WattBillGuide Electricity Cost Calculator automates these basic calculations and shows estimated daily, monthly, and yearly costs.

Use the WattBillGuide Electricity Cost Calculator for your own numbers.