How do I work out an appliance running cost?

Multiply the appliance power in kilowatts by the hours you use it to get the energy used, then multiply by your power price. This calculator does it for the cost per hour, week and year.

How do I find an appliance wattage?

It is usually on a label on the appliance or in the manual, in watts. Divide watts by 1000 to get kilowatts. Heaters and dryers draw a lot; small electronics draw little.

Which appliances cost the most to run?

High-wattage appliances used for long periods, like heaters, dryers and old fridges, cost the most. Working out the cost helps you decide what to use less or replace.

Appliance Running Cost Calculator

This calculator works out what any appliance costs to run, from its power draw and the hours you use it. You enter the wattage, usage and your power price, and it shows the cost per hour, week and year, helping you find the power-hungry appliances worth changing.

Appliance power (watts)

Hours used per day

Days used per year

Power price ($/kWh)

cost to run per year

Per hour$0

Per day$0

Energy per year0 kWh

Find the wattage on the appliance label or manual. High-wattage appliances used for long periods cost the most. Power prices change, so use your current rate. Estimate only.

How it works

The calculator converts the wattage to kilowatts, multiplies by the hours used to get the energy per day in kilowatt hours, then by the days per year and your power price. The result is the annual running cost, broken down to a cost per hour and per day. Comparing appliances this way shows which ones are quietly expensive and worth using less or replacing with an efficient model.

Worked example

A 2,000 watt heater used 4 hours a day for 150 days uses 8 kWh a day, 1,200 kWh a year. At 28 cents a unit that is about $336 a year, or roughly 56 cents an hour, which adds up over a winter.

Related calculators

Electricity Cost Calculator: power costs.
Hot Water Cost Calculator: hot water cost.
Home Heating Cost Calculator: heating cost.
Power Plan Comparison Calculator: compare power plans.

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