A complete step-by-step guide to understanding your utility bill, reading your meter, and calculating exactly what each device costs you.
Read guide →Learn what a kilowatt-hour actually means, how utilities use it to bill you, and how to translate appliance wattage into real dollars.
Read guide →Practical, proven strategies to cut your monthly electricity costs without sacrificing comfort — from quick wins to long-term upgrades.
Read tips →Electricity cost = (Wattage × Hours Used) ÷ 1000 × Price per kWh. For example, a 100W bulb running 5 hours at $0.16/kWh costs 8¢ per day. Our calculator does this automatically for any appliance.
A kilowatt-hour is the amount of energy consumed when 1,000 watts run for one hour. Utility companies bill by the kWh. The average US household uses about 877 kWh per month according to the U.S. Energy Information Administration.
The U.S. EIA reports the average residential electricity bill is about $140 per month (around 877 kWh at the national average rate of roughly 16¢/kWh). Actual costs vary significantly by state, season, and household size. Verify current data
Heating and cooling (HVAC) typically account for 40-50% of home electricity use. Water heaters, clothes dryers, electric ovens, refrigerators, and pool pumps are also major consumers. Our Full Home Estimator highlights your top spenders automatically.
Top strategies: upgrade to LED bulbs, use a programmable thermostat, seal air leaks, run full dishwasher and laundry loads, unplug idle electronics (phantom loads), and consider Energy Star appliances when replacing old units. See our Savings Tips page for a detailed breakdown.
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Absolutely. All calculations happen in your browser. We do not collect, store, or transmit any of your usage data, utility rates, or personal information. No cookies, no trackers.
Estimates are based on the wattage and usage hours you provide. Actual costs may vary due to fluctuating electricity rates, tiered pricing, time-of-use plans, and appliance efficiency variations. Use your utility bill to fine-tune the rate for best accuracy.
State averages range from about 10¢/kWh (Idaho, Washington) to over 40¢/kWh (Hawaii). Our calculator includes a state selector with the latest average residential rates from the U.S. EIA so you can estimate without looking up your exact bill.
A typical box or ceiling fan uses 50-100 watts. Running 8 hours per night at $0.16/kWh costs roughly 6-13¢ per night, or about $2-4 per month. Compared to air conditioning, fans are extremely inexpensive to operate.