Appliance Running Cost Calculator

Appliance running cost calculator for electricity per hour, day, and month

This appliance running cost calculator estimates how much electricity an appliance uses and what it costs to operate. The typical search intent here is simple: you want to know what a specific appliance is costing you on your power bill, based on its wattage, your electricity price per kilowatt-hour (kWh), and how many hours you use it each day.

Use it for appliances with a stated power rating such as kettles, heaters, air fryers, microwaves, washing machines, tumble dryers, dishwashers, pool pumps, or dehumidifiers. Enter the wattage from the label or manual, then enter your price per kWh from your bill or tariff. Add your typical daily usage time. The calculator returns a clear set of costs: per hour, per day, per 30-day month, and per year, plus the energy used in kWh.

The key output is the cost per month for your usage pattern, because that is usually what changes a decision. If the monthly figure looks high, you can quickly see how much you would save by reducing daily runtime by one hour. If you want a more realistic estimate for always-plugged-in devices, you can optionally include standby power and standby hours per day. That captures small continuous draws like routers, TVs, decoders, chargers, and appliances with clocks or always-on LEDs.

Assumptions and how to use this calculator

• The appliance power input is treated as an average running wattage for the time you use it.
• Electricity price is assumed constant per kWh, excluding time-of-use tiers, demand charges, and fixed fees.
• If “days per month” is blank, the calculator uses 30 days for a typical month.
• Standby power is optional and defaults to 0 W and 0 hours if you do not know it.
• This calculator estimates energy cost only and excludes maintenance, gas usage, water usage, or consumables.

Common questions

Where do I find the wattage for my appliance?

Check the sticker on the appliance body, the rating plate near the plug, the manual, or the manufacturer spec page. It is commonly listed as W (watts) or sometimes as kW (kilowatts). If you only have amps and volts, this calculator is not the right tool for that. Use a dedicated electrical power calculator to estimate watts first.

My appliance has a range of watts. What should I enter?

Use the value that best represents how you actually run it. For a heater with multiple settings, use the setting you usually use. For appliances with cycling behavior (like fridges or air conditioners), the label wattage may not reflect average use. In that case, your result is a rough upper-bound and you should treat the monthly cost as a conservative estimate.

What does “kWh per day” mean?

kWh is a unit of energy. A 1000 W appliance running for 1 hour uses 1 kWh. If you run a 2000 W heater for 2 hours, that is 4 kWh. Your electricity price per kWh is multiplied by your kWh usage to get cost. The calculator shows kWh so you can sanity-check the result and compare different appliances on the same basis.

How do I handle standby power and always-on devices?

If an appliance stays plugged in and draws power even when not actively used, enter the standby watts and standby hours per day. For example, a device that draws 5 W continuously has 24 standby hours per day. Standby costs are often small per day but become meaningful over a month, especially if you have multiple always-on devices.

Why does my result not match my monthly bill exactly?

Your bill usually includes fixed charges, taxes, and possibly tiered or time-of-use rates. Appliances also rarely run at a perfectly constant wattage. This calculator is designed for a practical estimate for one appliance under a consistent usage pattern. If you want to reconcile to a full bill, you need total household kWh and the full tariff structure, which is outside the scope of this page.