Appliance Electricity Cost Calculator

New to this? The four terms you need

Watts (W): How much power something uses at a given moment. It decides whether a power station or generator can run it at all.
Watt-hours (Wh): Power over time: watts × hours. It's the size of a battery, and decides how long things keep running.
Surge (starting watts): The short burst of extra power a motor needs to start, like a fridge, pump or AC. It lasts a split second but has to be covered.
LiFePO4: The battery type used in most new power stations. It lasts thousands of charge cycles and is the safer choice indoors.

The formula

Cost = Watts × Hours ÷ 1,000 × Rate per kWh

Utilities bill you in kilowatt-hours (kWh). One kWh is 1,000 watts running for one hour. That could be a 100 W TV for 10 hours or a 1,000 W microwave for one hour.

What common appliances cost per month

Appliance	Use	kWh / month	Cost at 18¢
Refrigerator (Energy Star)	24/7 (cycling)	~43	~$7.80
Space heater (1,500 W)	4 h/day	180	~$32.40
Window AC (700 W)	8 h/day	168	~$30.20
50" LED TV (100 W)	4 h/day	12	~$2.16
Wi-Fi router (20 W)	24/7	14.4	~$2.60
Desktop PC + monitor (250 W)	4 h/day	30	~$5.40

Find your real electricity rate

Your bill shows the total amount due and the kWh used. Divide the first by the second to get your all-in rate, including delivery charges and taxes. That number is more accurate than the "supply" rate alone. Some utilities also use time-of-use pricing, where evening power costs more. If yours does, run heavy appliances in the cheaper hours.

Planning backup power? A power station's capacity is measured in the same units: 1,000 Wh = 1 kWh. Use the power station size calculator to turn these numbers into a battery size.

Frequently asked questions

How do I calculate the cost of running an appliance?

Multiply the appliance's watts by the hours you use it per day and divide by 1,000 to get kWh. Then multiply by your electricity rate. For example, a 1,500 W heater for 4 hours uses 6 kWh, which costs about $1.08 per day at 18 cents per kWh.

What is the average electricity rate in the U.S.?

The U.S. average residential rate is in the high teens of cents per kWh, but it varies widely by state, from roughly 11 cents to well over 30 cents. For an accurate result, divide the total on your bill by the kWh used.

Which household appliances use the most electricity?

Heating and cooling (central AC, heat pumps, space heaters), electric water heaters, electric dryers and ovens are usually the biggest users. Electronics like routers and phone chargers cost very little.

Does unplugging appliances save money?

Standby (phantom) loads typically add 5–10% to a home's bill. Unplugging or using smart power strips for TVs, game consoles and computer setups can save a few dollars a month.

Appliance Electricity Cost Calculator

The formula

What common appliances cost per month

Find your real electricity rate

Frequently asked questions

Related guides

How Many Watts Does a Refrigerator Use? (Running, Starting and Per Day)