Appliance kWh Cost Calculator

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.