Electricity Cost Calculator
Estimate your appliances' energy consumption and find out the approximate cost on your power bill.
The electricity calculator estimates how much energy an appliance uses per month and the approximate cost of that on your power bill, based on the appliance's power rating, daily usage time, and the price your utility charges per kWh. It's useful for comparing appliances, planning a household budget, or figuring out which equipment weighs most on the bill.
How to use
- Enter the appliance's power rating in watts (W) — usually found on the label or in the manual.
- Enter how many hours per day and how many days per month the appliance is used.
- Fill in the price per kWh charged on your power bill and see the estimated monthly consumption and cost.
Worked example
An electric shower rated at 5,500 W used 40 minutes a day (about 0.67 hour) for 30 days consumes roughly 110 kWh in the month. At a rate of $0.90 per kWh, that's about $99 on the power bill from the shower alone — one of the appliances that weighs most on a household's consumption.
Frequently asked questions
How is consumption in kWh calculated?
Consumption (kWh) = Power (W) × Hours per day × Days per month ÷ 1000. For example, a 1000 W appliance used 3 hours a day for 30 days consumes 90 kWh in the month.
Where do I find my appliance's power rating?
It's usually on a label on the back or bottom of the appliance, or in the instruction manual, shown in watts (W) or sometimes kilowatts (kW, where 1 kW = 1000 W).
Where do I find the price per kWh to use in the calculator?
It's on your power bill, usually listed as the "rate" or "unit price" in your currency per kWh. The value can vary by region, tariff tier, and consumption bracket, so the result is an approximate estimate.
Which appliances use the most energy at home?
Heating and cooling appliances usually top the list: electric showers, air conditioners, irons, dryers, and the fridge (which, despite lower power, runs 24 hours a day). It's worth simulating each one in the calculator to find the culprits on your bill.
Are watts, kW and kWh the same thing?
No. Watts (W) and kilowatts (kW) measure power — how fast an appliance draws energy at a given moment (1 kW = 1000 W). The kilowatt-hour (kWh) measures energy used over time, and that's what the utility charges for. A 1000 W appliance running for 1 hour uses 1 kWh.
How can I reduce an appliance's consumption?
The two main ways are cutting usage time and switching to a more efficient model (lower power for the same job, like LED bulbs or an energy-rated air conditioner). Simulating before and after in the calculator helps you see the savings in real money.