Electricity Calculator

Wattage, hours of use, and your electricity rate — monthly cost and kWh.

W
hrs
$/kWh

The average US residential rate is around $0.13/kWh — check your utility bill for the actual rate on your tariff.

Monthly cost
$46.80
kWh/day
12.000
kWh/month
360.0
Annual cost
$569.40

The power rating on a device is its maximum draw — actual consumption is often lower if the device uses variable speed, has standby modes, or cycles on and off.

A worked example

A 1,500W space heater running 8 hours/day at $0.13/kWh costs about $46.80/month.

Frequently asked questions

What's a kilowatt-hour?

One kilowatt-hour is the energy used by a 1,000-watt device running for one hour — a 100W light bulb uses 1 kWh in 10 hours, while a 1,500W space heater uses 1.5 kWh per hour. It's the standard unit on electricity bills.

How do I find my electricity rate?

It's on your electricity bill, usually listed as a per-kWh charge. Rates vary significantly by utility, location, time of use, and season — the US average is around $0.13/kWh, but rates in some states run considerably higher.