Electricity Cost Calculator

Find out exactly how much it costs to run any appliance in your home.

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How Electricity Costs Are Calculated

Electricity is measured in kilowatt-hours (kWh). One kWh equals the energy consumed by a 1,000-watt appliance running for one hour. To find the cost of running any device, multiply its wattage by the hours of daily use, divide by 1,000 to convert to kWh, then multiply by your utility rate per kWh. The average U.S. residential electricity rate is approximately $0.17 per kWh as of 2025, though rates range from around $0.10 in states like Louisiana and Idaho to over $0.35 in Hawaii and parts of New England.

Daily kWh = (Watts x Hours Used) / 1,000
Daily Cost = Daily kWh x Rate per kWh
Monthly Cost = Daily Cost x 30

Common Appliance Wattages

A central air conditioner uses 2,000 to 5,000 watts, making it the largest electricity consumer in most homes. A space heater draws about 1,500 watts. Refrigerators use 100 to 400 watts but run 24/7, so their monthly consumption adds up. A clothes dryer uses 2,000 to 5,000 watts per cycle but runs only a few hours per week. LED light bulbs use 7 to 15 watts compared to 60 to 100 watts for incandescent equivalents, which is why lighting upgrades are one of the fastest ways to reduce electricity bills.

Gaming PCs can draw 300 to 800 watts under load, while a laptop typically uses 30 to 70 watts. A television uses 50 to 200 watts depending on size and technology. Standby power (phantom load) from devices in sleep mode accounts for 5 to 10% of total household electricity use. The Department of Energy estimates that phantom loads cost the average U.S. household about $100 per year.

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Understanding Your Electric Bill

Your electricity rate appears on your utility bill, usually listed as the price per kWh. Some utilities use tiered pricing where the first block of kWh (say 500) costs a base rate and additional usage costs more per kWh. Time-of-use (TOU) plans charge higher rates during peak hours (typically 2 PM to 7 PM on weekdays) and lower rates during off-peak times. If you are on a TOU plan, running heavy appliances like dishwashers and dryers during off-peak hours can meaningfully reduce your bill.

Beyond the per-kWh charge, most bills include a fixed customer charge ($5 to $15 monthly regardless of usage), distribution charges, and various riders or surcharges. This calculator focuses on the variable per-kWh cost, which is the portion you can control by adjusting your usage patterns.

Electricity Cost FAQ

What uses the most electricity in a home?
Heating and cooling account for 40 to 50% of residential electricity use, according to the U.S. Energy Information Administration. Water heating is next at roughly 12 to 15%, followed by major appliances at 10 to 15%, lighting at 5 to 10%, and electronics at 5 to 10%. The biggest single improvement for most households is upgrading HVAC equipment and improving insulation.
How much does it cost to charge an electric vehicle?
A typical EV with a 60 kWh battery charged from empty to full at the national average rate of $0.17 per kWh costs about $10.20. If the car gets 3.5 miles per kWh, a full charge provides roughly 210 miles of range. At about $0.05 per mile, EVs cost roughly one-third to one-half as much per mile as gasoline vehicles, though the exact comparison depends on local electricity and gas prices.
Does turning lights off actually save money?
Yes, though the savings depend on the bulb type. A 60-watt incandescent bulb left on for 8 unnecessary hours per day costs about $3 per month at $0.17 per kWh. An LED equivalent using 9 watts costs about $0.45 per month for the same duration. Over a whole house with 30 or more bulbs, the habit adds up, especially if you are still using older bulb types.

Where Your Electricity Goes

Heating and cooling eat 40-50% of the average home's electricity bill. Water heating takes another 12-15%. The rest splits between appliances, lighting, and electronics. Knowing which devices draw the most power helps you target the biggest savings first.

This calculator converts between watts, hours of use, and your electricity rate to show the actual cost of running any device. A space heater running 8 hours costs about $1.50/day. A gaming PC running 6 hours costs $0.50-$0.80/day. A phone charger costs about $2/year. Use it to find the expensive culprits and see our guide on lowering your electric bill for practical tips.