Convert watts to kWh
Appliances are often labeled in watts, while bills charge in kilowatt-hours. The calculator converts watts to kilowatts and multiplies by usage hours.
Electricity Cost Calculator
Estimate monthly electricity cost based on appliance usage and rate.
Changes display symbol only; no currency conversion.
Amountwatts
Appliance
wattage.
hours
Average daily run time.
days
Monthly usage days.
/
kWh
Cost per kWh from your bill.
units
Identical appliance count.
Results—
| Monthly cost | — |
| Daily cost | — |
| Monthly energy use | — |
| Annual cost estimate | — |
Daily kWh—
Rate used—
Total watts—
Currency—
This is a simplified planning estimate. Real-world costs, taxes, fees, rates, and timing can differ.
How it works
Estimate appliance electricity cost
This Electricity Cost Calculator estimates how much an appliance may cost to run based on wattage, hours used per day, days used per month, quantity, and electricity rate per kilowatt-hour.
It is helpful for comparing appliances, understanding high-usage devices, estimating home office costs, checking air conditioner or heater usage, and planning ways to reduce a monthly utility bill.
Actual bills can include fixed charges, tiered pricing, taxes, fuel adjustments, time-of-use rates, and other fees, so this tool focuses on the energy-use portion of the cost.
Estimate daily runtime
Usage time is a major driver of cost. A high-watt device used briefly may cost less than a lower-watt device running all day.
Use your local rate
Enter the price per kWh from your electricity bill. If your bill has several tiers, use an average rate for a quick practical estimate.
Scale for multiple devices
The quantity field helps estimate multiple identical devices such as bulbs, fans, monitors, chargers, refrigerators, or office equipment.
Frequently asked questions
The calculator converts watts to kilowatts by dividing by 1,000, multiplies by hours
used, multiplies by days used, and then multiplies by the electricity rate per kWh.
A kilowatt-hour, or kWh, is the amount of energy used by a 1,000-watt device running
for one hour. A 500-watt device running for two hours also uses 1 kWh.
Look at your utility bill for the price per kWh. If your bill includes tiered
pricing, divide the energy charge by total kWh to estimate an average rate.
Real bills may include fixed monthly charges, delivery fees, taxes, demand charges,
time-of-use rates, seasonal pricing, and fuel adjustments. Appliances can also cycle on and off instead of
running continuously.
Yes. The calculator shows an annual estimate based on the monthly result multiplied
by 12. For seasonal appliances, run separate scenarios for summer, winter, or heavy-use months.
No. It only changes the result symbol. Enter your rate in the same currency you
select, such as dollars per kWh or rupees per kWh.