🏡 Home Energy Usage Estimator

Add your household appliances with their wattage and daily usage hours to see your total estimated electricity cost.

Electricity Rate ($/kWh)

Every row is watts, hours and your rate

Each appliance is converted to kilowatt-hours a day and priced at the single rate at the top of the page:

kWh per day = watts / 1000 x hours per day
daily cost  = kWh per day x rate
monthly     = sum of daily costs x 30

The four defaults come to 5.5 kWh a day - 3.6 of it the fridge - which at $0.15 is 82.5 cents a day and $24.75 a month. Change the rate box before you read any of it: US residential rates run from about 11 cents to over 40, so the number on your own bill is the only one that makes this yours.

Two things that make the total wrong

Cycling appliances. The fridge default of 150 W for 24 hours assumes the compressor never stops. It runs perhaps a third of the time, so use the annual kWh from the energy label divided by 365, or enter about 8 hours instead of 24. That one change takes the estimate from $24.75 to $13.95.
Everything you did not list. Heating, cooling and hot water are usually more than half of a home's electricity, and standby loads add 5-10% more.

Reconcile before trusting it. A typical US home uses 850 to 900 kWh a month; if your appliance rows total 165 kWh, the missing 700 is where your money is going, not in the rows you listed.

Frequently asked questions

How many kWh a day does a house use?

The US residential average works out near 29 kWh a day, or 850 to 900 a month. All-electric homes with heat pumps and hot water run well above that; a small flat on gas heating can be under 10.

Why is my estimate lower than my actual electricity bill?

Because the big loads are hard to list. Air conditioning, electric heating and the water heater dominate most bills and none of them run on a simple hours-per-day schedule.

How do I enter a fridge or freezer that cycles on and off?

Take the annual kWh printed on the energy label and divide by 365 to get kWh a day, then work backwards to hours: a 150 W fridge rated at 400 kWh a year is about 1.1 kWh a day, which is 7.3 hours at full draw.