Find what an appliance costs to run. This free electricity cost calculator turns power, daily hours and your rate per kWh into the energy used and the cost per day, week, month and year.
Appliance
h / day
/ kWh
Enter the appliance’s power (check its label — W or kW), how many hours a day it runs, and your electricity rate per kWh (on your bill). Results update instantly.
Cost per month
—
Enter the details
Per day
—
Per week
—
Per year
—
Energy / day
—
Cost = power in kW × hours × rate. A 1500 W heater for 3 hours a day at $0.15/kWh costs about $0.68 a day. Monthly figures assume ~30.4 days; yearly assumes 365.
Use this free electricity cost calculator to find out how much an appliance costs to run. Enter its power, daily hours of use and your electricity rate to see the cost per day, week, month and year.
What this electricity cost calculator does
An electricity cost calculator works out the running cost of any appliance. From its power (watts or kW), how long it runs each day, and your rate per kWh, it shows the energy used and the cost over different periods.
How electricity cost is calculated
energy (kWh) = power in kW × hours used
cost = energy × rate per kWh
(watts ÷ 1000 = kW)
A 1500 W heater run 3 hours a day at $0.15/kWh uses 4.5 kWh and costs about $0.68 a day — roughly $20 a month.
Typical appliance running costs
Appliance
Power
Cost / hour @ $0.15
LED bulb
10 W
$0.0015
Laptop
50 W
$0.008
Fridge (running)
150 W
$0.023
Space heater
1500 W
$0.225
Air conditioner
2000 W
$0.30
Where to find the numbers
An appliance’s power rating is on its label or manual (in W or kW). Your rate per kWh is on your electricity bill. For always-on devices, use 24 hours a day; for occasional ones, estimate the realistic daily hours.
How to use the electricity cost calculator
Enter the appliance’s power (W or kW).
Enter hours used per day and your rate.
Read the cost per day, week, month and year.
Electricity Cost FAQ
How do I calculate the cost to run an appliance?
Multiply its power in kilowatts by the hours used, then by your rate per kWh. A 1500 W (1.5 kW) heater for 3 hours at $0.15/kWh costs about $0.68 a day.
How do I convert watts to kilowatts?
Divide watts by 1000. So 1500 W is 1.5 kW. The calculator accepts either unit.
What is a kWh?
A kilowatt-hour is one kilowatt of power used for one hour. It's the unit your electricity is billed in.
Where do I find my electricity rate?
On your electricity bill, usually shown as a price per kWh. Rates vary by provider, region and sometimes time of day.
Does it include standing charges or taxes?
No — it estimates the usage cost of the appliance itself. Your bill may add fixed charges, taxes and tiered or time-of-use rates.
Is the electricity cost calculator free?
Yes, this electricity cost calculator is completely free, needs no sign-up, and gives instant results in your browser.
