Appliance Cost Calculator — Daily, Monthly & Yearly

Electricity is billed by the kilowatt-hour — one kilowatt of power used for one hour. To find what an appliance costs to run, you only need three things: how many watts it draws, how many hours a day it runs, and your electricity rate. The energy per day is watts × hours ÷ 1000 in kilowatt-hours, and the cost is that figure times your price per kWh. This calculator does the arithmetic and projects it out to a month and a year so small daily numbers become the amounts you actually see on a bill.

Wattage comes from the appliance label, its nameplate, or a plug-in energy meter; the last is the most accurate because many devices draw less than their rated maximum. Hours per day should reflect real use — a fridge compressor cycles on and off, so its effective run time is well below 24 hours even though it is always plugged in. Your price per kilowatt-hour is on your electric bill; the U.S. average is often near $0.15 to $0.17, but rates vary widely by region and by time of day.

The calculator uses 365 days for the yearly figure and divides that by 12 for the monthly figure, so the day, month, and year numbers stay consistent with each other. This is a budgeting tool, not a code calculation — it estimates cost only, and does not involve any wiring decisions. It pairs well with the generator worksheet and the amps-watts-volts converter when you are planning loads.