How to calculate the electricity cost of an appliance
Every appliance carries a power rating in watts, and your bill charges per kilowatt-hour. The cost of a device is simply its kilowatts multiplied by how many hours it runs, multiplied by your price per kWh. That short formula tells you which devices eat your electricity bill.
The watt-to-cost formula
Convert watts to kilowatts by dividing by 1000. A 2000-watt heater is 2 kW. Multiply by the hours you run it in a day, then by the days in the period. That gives consumption in kWh. Multiply by your unit price — for example 2 kW times 3 hours is 6 kWh per day; at a price of 0.30 per kWh that device costs 1.80 per day.
Small devices mislead because they look harmless: a 60-watt TV on 6 hours a day uses about 10.8 kWh per month, while an idle or old fridge may quietly pass it.
- Energy (kWh) = watts ÷ 1000 × hours × days.
- Cost = energy × price per kWh.
- Check your bill for the exact rate you pay.
Estimate it automatically with FreetoolsY
The Electricity Cost Calculator takes the four inputs — wattage, hours per day, days per month and your kWh price — and returns monthly and yearly consumption plus the expected cost for each period. Adjust the hours and watch the annual cost move live.
Where to save first
Start with high-power, frequently used devices: heaters, irons, kettles and dryers. Cut the hours there before replacing anything, then compare replacement options with the same formula. Small changes in daily usage compound into large annual savings.