Appliance Running Cost Calculator
Work out what an appliance costs to run per day, month and year from its wattage, hours of use and your electricity rate.
Last checked 10/11/2026. Sources: South Australian Government: Calculate appliance running costs; Australian Energy Regulator: The Default Market Offer (tariff caps 2026-27); Essential Services Commission (Victoria): Victorian Default Offer price review 2026-27.
Guide
How the cost is worked out
Energy in kWh = (watts × hours) ÷ 1,000. Multiply by the days of use, then by your usage rate per kWh. The South Australian Government’s guide uses the same method.
Example. A 2,000 W heater running 3 hours uses 6 kWh. At 33.14c per kWh (the Ausgrid flat-rate Default Market Offer cap) that is $1.99.
The electricity rate
The Australian Energy Regulator sets Default Market Offer (DMO) caps for the single-rate residential tariff in New South Wales, South East Queensland and South Australia for 2026-27. Pick your network area to use its cap as a starting point. The DMO is the most a retailer can charge on a standing offer, so many people pay less on a market offer; use your bill’s usage rate for an exact answer. Elsewhere, enter your own rate. The daily supply charge is fixed and is not part of an appliance’s running cost.
Wattage and duty cycle
Check the label for the wattage, remembering that it is often the maximum. Appliances with thermostats or motors, such as fridges and heaters, only run part of the time, so use the "runs this % of the time" box. The preset wattages are typical figures, not data for your model. The Energy Rating label shows annual kWh for fridges and other labelled appliances.
What is not included
Daily supply charges, time-of-use tariffs, controlled load and solar are not included.
Common questions
How much does it cost to run a heater?
A 2 kW heater running continuously uses 2 kWh an hour, which is about 66c an hour at 33.14c per kWh.
Does the rate include GST?
The AER page does not say whether the capped rates include GST, so compare with the usage rate on your own bill.
Do standby appliances cost much?
A device drawing 5 W all year uses about 44 kWh, about $14.50 at 33.14c per kWh. Many together can add up.
Why does my fridge use less than its wattage suggests?
Because the compressor cycles on and off. Use the duty cycle box, or the annual kWh on the Energy Rating label.
What next?
- Thinking of replacing it? See how long a more efficient one takes to pay for itself. Energy Upgrade Payback Calculator
- Running a heater? Compare it with a heat pump. Heater vs Reverse-Cycle Air Conditioner Cost Calculator