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How to calculate the electricity cost of an appliance

You want to know what an appliance adds to the bill. You will read its watts, estimate how long it runs and multiply by your price per kWh. A 1000 W air conditioner running 8 hours a day for a month uses 240 kWh; at 0.15 that is 36.00. Nothing leaves this tab.

6-minute read

Today's result Cost for the period, energy in kWh, cost and kWh per day, and cost per year, in whatever currency you type.

Open the electricity cost calculator with the appliance label and your latest bill at hand. Fridges and air conditioners cycle on and off, so their real use is lower than the label. Nothing is uploaded.

Open Electricity cost calculator
Contents

  1. Know the formula

    Energy in kWh = watts × hours ÷ 1000. Cost = kWh × price per kWh. A 1000 W heater running one hour uses exactly 1 kWh.

    kWh = watts × hours ÷ 1000; cost = kWh × price per kWh.
    kWh = watts × hours ÷ 1000; cost = kWh × price per kWh.

  2. Open Electricity cost calculator on cv.cm

    A 1000 W air conditioner, 8 hours a day, 30 days at 0.15 per kWh is filled. The cost sits on the right. Nothing is uploaded.

    Open Electricity cost calculator

  3. Find the watts

    Pick a preset or type the watts from the label or manual. If the label gives amps, multiply by the voltage: 5 A × 220 V = 1100 W.

  4. Enter hours, days and price

    Type the hours a day it runs and the number of days. Take the price per kWh from your bill: energy charge ÷ kWh used. For several identical devices set How many.

  5. Read the result

    The air conditioner: 240 kWh, 36.00 for the month, 1.20 a day, 438.00 a year. A 10 W LED bulb for 5 hours a day uses 1.5 kWh a month: 0.30 at 0.20 a kWh.

    1000 W × 8 h × 30 days = 240 kWh; at 0.15 that is 36.00 a month.
    1000 W × 8 h × 30 days = 240 kWh; at 0.15 that is 36.00 a month.

  6. Account for cycling and standby, then copy

    A 150 W fridge on 24 hours shows 3.6 kWh a day, but the compressor runs about a third of the time, so expect nearer 1.2. Standby of a few watts all year adds up to tens of kWh. Copy puts the numbers on the clipboard.

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FAQ

Can I calculate appliance electricity cost free online?

Yes. cv.cm does the math in this tab. Nothing is uploaded.

How much does a 1000 W appliance cost per hour?

It uses 1 kWh an hour, so the cost equals your price per kWh, for example 0.15.

How do I convert amps to watts?

Multiply amps by volts: 5 A at 220 V is 1100 W, at 120 V it is 600 W.

Why is my fridge's real use lower?

The compressor runs only part of the time, often about a third, so the label watts overstate daily use.

Which currency does it use?

Whatever you type for the price. The result is in the same currency.