Appliance Running Cost Calculator
Calculate the daily, monthly, and annual electricity cost of any home appliance.
Enter wattage, hours per day, and your utility rate to see the bill impact.
Every appliance that draws power costs money to run, but the amounts surprise people. A desktop computer running 8 hours a day at 200 watts costs about $5-6 per month at U.S. average rates. A 1,500-watt space heater running the same hours costs $35. Same hours, ten times the cost.
The formula
kWh per day = (watts / 1000) x hours per day
Monthly cost = kWh per day x days per month x rate per kWh
Annual cost = monthly cost x 12
The kilowatt-hour (kWh) is the unit utilities use for billing. One kWh means 1,000 watts running for one hour — or a 100-watt bulb running for 10 hours.
Typical wattages
Refrigerator: 100-200 W (runs roughly 8-10 effective hours per day cycling on and off). Electric oven: 2,000-5,000 W during preheat and active cooking. Window AC: 500-1,500 W by BTU rating. Clothes dryer: 4,000-6,000 W. Dishwasher: 1,200-2,400 W per cycle. LED TV (55 inch): 70-100 W. Desktop with monitor: 150-300 W. Laptop: 30-70 W. For appliances with cycles (fridge, AC), the nameplate wattage is peak draw — effective average wattage is usually 40-60% of that.
U.S. electricity rates average around $0.13/kWh nationally, but range from $0.09 in Louisiana to over $0.40 in Hawaii. Check your last utility bill for your specific rate — it is usually listed as cents per kWh. If your utility uses tiered pricing, your marginal rate (what the next kWh costs) may be higher than the average shown on your bill.
Many utilities also charge a flat monthly service fee on top of usage. This calculator shows only the variable usage cost — your full bill will be higher.