Energy converter

Electricity Cost Calculator

Estimate how much an appliance costs to run from its wattage, run time, and energy rate.

How Electricity Cost works

The cost of running an appliance depends on three things: its power in watts, how long it runs, and the price you pay per kilowatt-hour. Multiply them together to get the running cost.

First convert watts to kilowatts by dividing by 1,000, then multiply by the hours of use to get energy in kWh. Multiplying that by your electricity rate gives the cost — scale up by 30 or 365 for monthly and yearly estimates.

Formula

1Cost = (W ÷ 1000) × hours × rate

Energy (kWh) = watts ÷ 1000 × hours; cost = energy × price per kWh.

Electricity Cost conversion table

Reference Table5 rows

Running cost at $0.15/kWh for 3 hours of use per day.
Appliance Power↕	Energy/Day↕	Cost/Day↕	Cost/Year↕
100 W	0.3 kWh	$0.045	$16.43
500 W	1.5 kWh	$0.225	$82.13
1,000 W	3 kWh	$0.45	$164.25
1,500 W	4.5 kWh	$0.675	$246.38
2,000 W	6 kWh	$0.90	$328.50

💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Electricity Cost

How do you calculate electricity cost?

Multiply the appliance power in kilowatts by the hours used and your rate per kWh. For example, a 1,500 W heater for 3 hours at $0.15/kWh costs 1.5 kW × 3 h × $0.15 = $0.68 per day.

What is a typical electricity rate?

US residential rates average around $0.15–0.18 per kWh but vary widely by state and provider. Check the 'rate' or 'price per kWh' line on your utility bill for your exact figure.

How much does it cost to run a 1500W heater?

At $0.15/kWh, a 1,500 W heater costs about $0.23 per hour. Run 3 hours a day, that is roughly $0.68 per day, about $20.50 per month, or $246 per year.

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