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Electricity calculators
Work out kWh, running costs and your real price per kWh for any appliance or bill.
New to the topic? Read What Is a Kilowatt-Hour (kWh)? Meaning, kW vs kWh and Cost.
FAQ
Frequently asked questions
How do I calculate electricity cost?
Multiply the device’s watts by the hours it runs and divide by 1,000 to get kWh, then multiply by your price per kWh. A 1,500 W heater running 4 hours uses 6 kWh, which costs $1.09 at 18.2¢ per kWh.
What is the average price of electricity in the US?
The US average residential price was 18.16¢ per kWh in August 2026, according to the EIA Electric Power Monthly. Prices vary widely by state, from about half the average to more than double it.
What is the difference between kW and kWh?
A kilowatt (kW) measures power, the rate at which energy is used. A kilowatt-hour (kWh) measures energy, power used over time. A 1 kW appliance running for one hour uses 1 kWh.
How do I find my price per kWh?
Divide your total bill by the kWh used shown on the bill. For the price of each extra kWh, subtract fixed monthly charges first, then divide by the kWh used.
Which appliances use the most electricity?
Heating and cooling, water heaters, clothes dryers and electric vehicle charging are usually the largest loads. Use the electricity usage calculator to compare appliances with your own hours and price.
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