Calculate electricity cost per appliance
Enter an appliance’s wattage, daily usage, and your price per kWh to get its daily, monthly, and annual cost.
Common appliance electricity costs
Typical wattage and monthly cost for common household appliances at $0.16/kWh.
| Appliance | Typical watts | Typical use | Monthly cost |
|---|---|---|---|
| Refrigerator | 150W | 24 hrs/day | $17.28 |
| Window AC | 1200W | 10 hrs/day | $57.6 |
| Central AC | 3500W | 8 hrs/day | $134.4 |
| Space heater | 1500W | 8 hrs/day | $57.6 |
| LED TV (55in) | 100W | 5 hrs/day | $2.4 |
| Washing machine | 500W | 0.5 hrs/day | $1.2 |
| Electric dryer | 3000W | 1 hrs/day | $14.4 |
| Microwave | 1000W | 0.25 hrs/day | $1.2 |
| Desktop computer | 200W | 6 hrs/day | $5.76 |
| Ceiling fan | 75W | 8 hrs/day | $2.88 |
| Incandescent bulb | 60W | 5 hrs/day | $1.44 |
| LED bulb | 10W | 5 hrs/day | $0.24 |
| Electric water heater | 4000W | 3 hrs/day | $57.6 |
| Dishwasher | 1800W | 1 hrs/day | $8.64 |
Have a different wattage or usage pattern? Use the electricity cost calculator above.
About the electricity cost calculator
The math behind this calculator is simple, but the units trip people up: appliances are labeled in watts, while utilities bill in kilowatt-hours (kWh). Dividing watts by 1000 converts to kilowatts, and multiplying by the hours used gives kilowatt-hours — the same unit on your electric bill. Multiply that by your price per kWh and you get the actual dollar cost of running the appliance.
The $0.16 per kWh default here is only a rough U.S. national average — real rates vary a lot by state, utility provider, and even time of day on plans with time-of-use pricing. For an accurate number, check a recent electric bill for your actual rate per kWh (it's usually printed on the usage or charges section) and enter that instead of the default.
There's an important difference between an appliance's rated or nameplate wattage and what it actually draws on average. A refrigerator's compressor cycles on and off rather than running continuously, and a window AC unit's draw varies as it cycles to maintain temperature — so nameplate wattage (often printed on a sticker inside the unit) tends to overstate real-world average draw. The appliance chart on this page lists realistic running averages rather than peak or nameplate figures, which is why your actual results may differ from a number you find printed on the appliance itself.
Small always-on loads are easy to underestimate because a single number in watts looks tiny — a WiFi router at 10 watts or a phone charger left plugged in barely registers. But this calculator's daily-to-annual multiplier (days × 365) magnifies even small loads, which is exactly how "phantom load" or standby power from chargers, routers, and devices left in sleep mode adds up to a real line item on an annual electric bill.
Keep in mind this is a simplified, linear estimate. Real electric bills often include tiered rate structures (where the price per kWh increases after a usage threshold), demand charges for commercial accounts, seasonal rate changes, and fixed monthly delivery or service fees layered on top of usage charges — none of which this calculator models. Treat the result as a close estimate of the appliance's own usage cost, not a prediction of your total bill.
Common electricity cost examples
Popular appliance wattage and usage combinations, already calculated.
By appliance
Electricity cost calculator questions
How to estimate the cost of running an appliance.
How do I calculate the electricity cost of an appliance?
Multiply the appliance's wattage by the hours you use it per day, divide by 1000 to get kilowatt-hours (kWh), then multiply by your price per kWh. For example, a 1500W space heater run for 8 hours at $0.16/kWh costs 1500/1000 × 8 × 0.16 = $1.92 per day.
How much does it cost to run a space heater?
A typical 1500W space heater run 8 hours a day costs about $1.92 per day, $57.60 per month, and $700.80 per year at $0.16/kWh. Running it fewer hours or at a lower wattage setting reduces the cost proportionally.
How do I convert watts to kWh?
Divide the wattage by 1000 to get kilowatts, then multiply by the number of hours the device runs. A 1000-watt appliance run for 1 hour uses exactly 1 kWh.
What is the average price per kWh in the US?
The U.S. national average is roughly $0.16 per kWh, which is the default this calculator uses, but rates vary significantly by state and utility. Check a recent electric bill for your actual rate for a more accurate result.
How much does it cost to run an air conditioner all day?
A 1200W window AC unit run 10 hours a day costs about $1.92 per day, or roughly $57.60 per month at $0.16/kWh. A larger 3500W central AC system run 8 hours a day costs closer to $4.48 per day, or about $134.40 per month.
Does wattage on an appliance label reflect actual usage?
Not exactly. The nameplate or rated wattage is typically the maximum draw, but many appliances — especially refrigerators and air conditioners — cycle on and off, so their average running wattage is often lower than the rated number. This calculator's appliance chart uses realistic running averages rather than peak nameplate figures.
Sources & references
The formulas and guidelines used on this page are based on publicly available data from: