Appliance Energy Use Calculator
See what each appliance adds to your bill — pick a common preset or enter your own watts.
Updated
Typical running watts — override with your label's figure.
From your bill — the US average is about $0.175.
You need
$18.90/month
108.0 kWh a month at this usage
- Energy per month
- 108.0 kWh
- Cost per year
- $226.80
- Energy per year
- 1,296.0 kWh
In short
How much does an appliance cost to run per month?
Monthly cost is watts divided by 1,000, times hours per day, times 30, times your rate. The default 150 W refrigerator running around the clock uses 108 kWh a month and costs $18.90 at $0.175 per kWh, which comes to 1,296 kWh and $226.80 across a year. Runtime matters as much as wattage.
Preset wattages are typical running figures rather than your exact unit, so the label on the appliance or a plug-in meter reading will always beat them.
How to use the appliance energy use calculator
Pick an appliance from the list and the tool fills in a typical running wattage you are free to edit, then set how many hours a day it runs and enter your electricity rate, and you get the energy and the cost both per month and per year. The rate is the input that swings the answer hardest.
The Energy Information Administration put the US residential average at 18.44 cents per kilowatt-hour in May 2026 in its Electric Power Monthly released 23 July 2026, but the same table showed Idaho at 12.35 cents and Hawaii at 52.00 cents in that one month, so a national average is a placeholder rather than an answer. Take a recent statement, divide the amount due by the kilowatt-hours it covered, and enter that.
108 kWh
Fridge, per month
150 W running 24 hours a day
$18.90
Monthly cost
at $0.175 per kWh
$226.80
Across a year
1,296 kWh at the same rate
The second pattern is the always-on versus the occasionally-enormous split, and it is the reason the hours field matters as much as the watts field. A refrigerator draws only about 150 watts, but it never switches off, so it quietly accumulates 108 kWh a month and often ends up the single largest plug load in a home.
A 3,000 W clothes dryer is twenty times the power but runs perhaps an hour at a time, so it lands at 90 kWh a month across a daily load. Both belong on the bill and runtime decides which one wins, which is why guessing at hours undoes any care you took over wattage.
Know the wattage already?
The electricity cost calculator skips the preset list entirely and prices any device straight from the watts, hours and days you enter.
Open the electricity cost calculator →Do
- Switch to Custom and enter the wattage printed on your own appliance.
- Enter genuine runtime: 24 hours for a refrigerator, about one for a dryer load.
- Read the annual figure when deciding whether replacing an appliance pays.
- Cross-check the result against the EnergyGuide estimated annual kilowatt-hours where that label exists.
Don't
- Feed nameplate watts into a cycling appliance, whose compressor is idle much of each hour.
- Leave the rate at a national average when Idaho is 12.35 cents and Hawaii 52.00.
- Hunt savings among the electronics before the things that make heat.
- Treat the monthly total as your bill, since service and delivery charges do not scale with one appliance.
Every preset in this tool, run at a plausible daily runtime, so you can see where a household bill actually goes. Wattages are the running figures built into the calculator; the kilowatt-hours and costs are computed from them at the runtime shown, a 30-day month, and the tool default rate.
| Appliance and running watts | Hours per day assumed | kWh per 30-day month | Cost per month at $0.175/kWh | Cost per year |
|---|---|---|---|---|
| Space heater, 1,500 W | 8 | 360 | $63.00 | $756.00 |
| Window air conditioner, 1,200 W | 8 | 288 | $50.40 | $604.80 |
| Space heater, 1,500 W | 4 | 180 | $31.50 | $378.00 |
| Refrigerator, 150 W | 24 | 108 | $18.90 | $226.80 |
| Clothes dryer, 3,000 W | 1 | 90 | $15.75 | $189.00 |
| Dishwasher, 1,800 W | 1 | 54 | $9.45 | $113.40 |
| Desktop PC, 200 W | 8 | 48 | $8.40 | $100.80 |
| Ten devices on standby, 3 W each | 24 | 21.6 | $3.78 | $45.36 |
| Washing machine, 500 W | 1 | 15 | $2.63 | $31.50 |
| LED TV, 100 W | 5 | 15 | $2.63 | $31.50 |
| Ceiling fan, 60 W | 8 | 14.4 | $2.52 | $30.24 |
| Microwave, 1,000 W | 0.25 | 7.5 | $1.31 | $15.75 |
| Incandescent bulb, 60 W | 4 | 7.2 | $1.26 | $15.12 |
| LED bulb, 9 W | 4 | 1.08 | $0.19 | $2.27 |
Which appliances actually dominate a bill?
The appliances that dominate a bill are the ones that make heat, because turning electricity into warmth is expensive by nature. Electric resistance loads such as space heaters, clothes dryers, water heaters, ovens, and stovetops pull between 1,500 and 5,000 watts and dwarf anything with a screen or a processor in it.
A 1,500 W space heater running eight hours a day is 360 kWh a month, while a 100 W television running five hours a day is 15 kWh. That is a factor of twenty-four between two things people worry about roughly equally. If you are hunting for savings, start with anything that produces heat and only then look at the electronics.
Read it: The heater runs a third of the hours the refrigerator does and still uses more than three times the energy; making heat is expensive by nature.
Computed as (watts / 1000) × hours per day × 30, from the preset running wattages.
The formula, worked line by line
Monthly energy is the appliance power multiplied by its daily runtime across a 30-day month, and cost is that energy multiplied by your rate. The annual figures are simply twelve of those months, which keeps the two horizons consistent rather than mixing a 30-day month with a 365-day year.
Watts are divided by 1,000 to become kilowatts so the units line up with the kilowatt-hours your utility meters and bills. Everything difficult sits in the two inputs rather than the arithmetic: the wattage has to be the real running draw rather than a nameplate ceiling, and the hours have to be genuine runtime rather than time plugged in.
monthly kWh = (watts / 1000) x hours per day x 30
monthly cost = monthly kWh x rate
annual kWh = monthly kWh x 12
annual cost = monthly cost x 12- Running power
- 150 W = 0.15 kW
- Runtime
- 24 hours × 30 days = 720 hours
- Energy
- 0.15 × 720 = 108 kWh
- Rate
- $0.175 per kWh
- Monthly cost
- $18.90
Across twelve months that is 1,296 kWh and $226.80. Price the same 108 kWh at the May 2026 US average of 18.44 cents and it becomes $19.92.
Now set that against a 1,500 W space heater running eight hours a day: 1.5 kW times 8 hours times 30 days is 360 kWh a month and $63.00, more than three times the refrigerator despite running a third of the hours. The heater wins on power, the fridge wins on persistence, and the bill counts both. That is the entire lesson of this calculator, and it is why the hours field is not a formality.
Questions people ask
How much does it cost to run a refrigerator?
A typical 150 W refrigerator running around the clock uses 108 kWh a month, which is $18.90 at $0.175 per kWh, or 1,296 kWh and $226.80 across a year. That frequently makes it the single largest plug load in a home, not because it draws much power but because it never stops. Newer units certified under Energy Star draw noticeably less, so read the wattage from your own nameplate or the estimated annual kilowatt-hours from the EnergyGuide label and enter that instead of the preset.
Which appliances use the most electricity?
The heat-makers, without much competition: space heaters, clothes dryers, electric water heaters, ovens, stovetops, and air conditioners, which run from 1,500 to 5,000 watts. Electronics are small by comparison, since a television, a laptop, and a phone charger together rarely match a single heating element. The other large contributor is anything that runs continuously, where a modest wattage plus 8,760 hours a year adds up to a serious total. A refrigerator at 150 W is the textbook case, reaching 108 kWh a month purely on persistence.
Why is the running wattage lower than the nameplate?
The nameplate lists the maximum the appliance may draw, and sometimes a startup surge on top of that, because it exists to size the circuit rather than to predict your bill. Appliances that cycle on and off, meaning refrigerators, freezers, air conditioners, and anything thermostat-controlled, only pull full power while the compressor or element is energised and idle for the rest of each hour. The presets in this tool use typical running watts rather than nameplate maximums for exactly that reason. For an exact figure, a plug-in energy monitor reads the real draw at the outlet.
How many kWh does an appliance use per month?
Multiply its watts by the hours it runs each day, divide by 1,000, then multiply by 30. A 150 W refrigerator at 24 hours is 108 kWh, a 100 W television at 5 hours is 15 kWh, a 1,200 W window air conditioner at 8 hours is 288 kWh, and a 1,500 W space heater at 8 hours is 360 kWh. The tool does the arithmetic for you and adds the annual figure by multiplying the month by twelve, plus the cost at whatever rate you enter.
How do I lower what an appliance costs to run?
Cut runtime first, because it is the biggest lever on anything you can switch off sooner or run less often. Replace the always-on heat loads next, since an ageing refrigerator or electric water heater runs continuously and an efficient replacement pays back every hour of every day rather than only when you remember. If you are on a time-of-use tariff, shift heavy discretionary loads such as laundry and dishwashing into the off-peak window. Chasing small electronics feels productive but rarely moves a bill in a way you can measure.
Sources
Where the constants and formulas on this page come from. Each line names the figure it backs.
The 18.44 cents per kWh US residential average for May 2026 and the 12.35 cent Idaho to 52.00 cent Hawaii state spread that month.
Electric Power Monthly, Table 5.6.A — Average price of electricity by state — US Energy Information Administration, May 2026
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