Energy converter

Appliance Energy Cost Calculator

Estimate the energy footprint and running cost of household appliances.

How Appliance Energy Cost works

Running appliances adds up on your monthly electricity bill. To calculate how much a device costs to run, multiply its active power in kilowatts by its usage hours and utility rate.

This calculator makes it easy to compare energy-hungry devices like portable air conditioners and space heaters against small loads like LED light bulbs or laptops.

Formula

1Daily kWh = Power(Watts) × Hours(h) ÷ 1,000

2Cost = Daily kWh × Days × Utility Rate

Standard calculations use a billing cycle of 30 days.

Appliance Energy Cost conversion table

Reference Table5 rows

Estimated monthly costs of standard home items (assumes 8 hours/day, $0.15/kWh rate).
Device↕	Power Rating (Watts)↕	Monthly Energy (kWh)↕	Monthly Cost ($)↕
LED Bulb	10 W	2.4 kWh	$0.36
Smart TV	100 W	24 kWh	$3.60
Gaming PC	400 W	96 kWh	$14.40
Microwave (continuous)	1,000 W	240 kWh	$36.00
Space Heater	1,500 W	360 kWh	$54.00

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

FAQ: Appliance Energy Cost

How do you calculate appliance electricity cost?

Multiply the device wattage by daily run hours, divide by 1,000 to convert to kilowatt-hours (kWh), and then multiply by your utility's electricity rate per kWh.

What is the average electricity rate?

Residential electricity rates vary widely. In the United States, the national average is approximately $0.15 to $0.17 per kilowatt-hour (kWh), though some areas have much higher rates.

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