Appliance Cost Calculator
Find out what a single device costs per month to run.
Updated 2026-02-12
Useful for estimating the cost of heaters, kettles, dryers, air conditioners, computers, and other household devices.
How appliance electricity cost is calculated
This calculator estimates the monthly electricity cost of running a single appliance based on three simple inputs: wattage, hours used per day, and electricity price per kilowatt-hour (kWh). The formula is straightforward: watts are converted into kilowatts, multiplied by hours of use, and then multiplied by the number of days in a month.
For example, a 1,500-watt appliance used for 2 hours per day consumes about 3.0 kWh per day. Over 30 days, that becomes 90 kWh. If electricity costs $0.12 per kWh, the estimated monthly energy cost would be about $10.80.
Why appliance wattage matters
Appliances with heating elements usually consume much more electricity than devices used for electronics or lighting. Space heaters, ovens, kettles, clothes dryers, and electric water heating equipment tend to be some of the largest electricity users in a home. Lower-wattage devices such as laptops, routers, and LED lamps usually cost much less to operate, even when used for many hours.
This is why understanding wattage is useful. It helps households identify which devices are likely to make the biggest difference on an Ontario electricity bill.
Why real costs can vary
This tool estimates the energy portion of appliance use, but actual Ontario electricity bills also include delivery charges, Global Adjustment, and taxes. In addition, some appliances do not run continuously at their full rated wattage. Refrigerators, freezers, and air conditioners cycle on and off, so their real monthly electricity use may be different from a simple nameplate calculation.
That means this calculator works best as an educational estimate rather than an exact billing tool. It is useful for comparing devices and understanding general cost patterns.
Which appliances usually cost the most to run?
In many homes, the most expensive appliances to run are those that produce heat or move large amounts of air. Common examples include:
- portable electric heaters
- electric baseboards
- clothes dryers
- ovens and stovetops
- air conditioners
- electric water heating systems
By contrast, many electronics use less electricity than people assume. The biggest savings opportunities often come from heating, cooling, drying, and hot water rather than from small plug-in devices.