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Appliance cost estimate
Estimate how much an appliance costs to run per day, per month, and per year. This helps with household budgeting, comparing devices, and checking whether a heater, fan, computer, or other appliance is expensive to leave on.
Estimate running cost
Use the appliance wattage, your average daily usage, your electricity rate, and the number of identical appliances you want to estimate together.
How to read the result
The daily estimate is best for short comparisons, but the monthly and yearly estimates are usually more useful for real budgeting. A small daily cost can become noticeable if the appliance runs every day, while a high-wattage appliance may matter less if it is only used for short periods.
If the monthly result is low, this appliance is probably not a major reason for a high electricity bill. If the yearly result is large, use it as a signal to compare usage habits, check whether the input assumptions are reasonable, or measure the appliance directly.
When the result looks higher than expected, check the hours used per day before changing the wattage. Runtime is often the biggest driver of appliance cost, especially for heaters, dehumidifiers, desktop PCs, and devices that run for many hours at a time.
If you want to convert wattage into energy use first, use the Watts to kWh Calculator. To compare all electricity-related tools and guides, start from the Electricity Cost Calculators hub. If you already know kWh, use the kWh to Cost Calculator.
Result interpretation
A small daily estimate can still matter when the appliance runs every day. The monthly number is usually the better signal for a regular habit, while the daily number is useful for comparing one appliance with another.
If the result looks too high or too low, rerun the calculator with a different daily runtime before changing the wattage. For many household appliances, the difference between occasional use and daily use matters more than a small wattage difference.
If the wattage is only a label value and the device cycles or changes power draw, a measured kWh reading can be a better next check than guessing a new wattage.
Example
A portable heater can have a high wattage, but the real cost depends on how long it runs. For example, a 1,500 W heater used for 3 hours per day will have a very different monthly cost from the same heater used for 8 hours per day.
Use the daily estimate to compare one evening of heating, the monthly estimate to understand winter bill impact, and the yearly estimate only if the heater is used across many months. If the monthly number feels high, try recalculating with fewer daily hours to see how much runtime changes the result.
Example
A 500 W dehumidifier active for 6 hours per day uses 3.00 kWh because 500 x 6 / 1000 = 3.00. At 0.20 per kWh, the estimated usage cost is 0.60 per day.
The important input is active runtime, not just plugged-in time. If the compressor runs longer during humid weather, the daily and monthly estimates can rise quickly even though the wattage did not change.
Calculation logic
Electricity use is estimated by multiplying wattage by hours used per day and by the number of identical appliances, then dividing by 1000 to convert watts into kilowatts.
Formula: cost = (wattage x hours per day x quantity / 1000) x electricity rate
Monthly cost uses a 30 day month. Yearly cost uses 365 days with the same average daily usage pattern.
Notes and caveats
Common uses
This kind of estimate is practical when comparing device habits, tracking home energy costs, or checking whether one appliance could be contributing to a noticeable part of the bill.
Check whether two similar devices or two different runtime assumptions have meaningfully different running costs.
Use it for devices that run many hours per day, such as routers, fans, dehumidifiers, or gaming PCs.
Run the numbers for portable heaters or window AC units to understand why energy costs rise in some months.
FAQ
Check the label on the appliance, the user manual, or the product page. Some devices list amps instead of watts, in which case you may need the voltage to estimate wattage accurately. The appliance wattage guide explains where to look.
That is fine. Enter the electricity rate in your own currency per kWh. The result follows the currency you use for the rate.
Real bills can include taxes, delivery charges, tiered pricing, or changing daily usage. This tool is best used as a fast estimate rather than a full utility bill total. For the most common reasons behind the gap, read why your electric bill is higher than the calculator estimate.
Yes. Increase the quantity field if you are estimating several identical appliances with the same wattage and daily usage pattern.
Use a realistic daily average. For example, if you use a dehumidifier for 4 hours on some days and 8 hours on humid days, enter an average that reflects a typical week rather than the longest possible day.
Wattage only shows how much power the appliance uses while running. A high-wattage appliance used briefly can cost less than a lower-wattage appliance that runs all day.
This calculator is based on hours per day. If you only know monthly usage, divide the monthly hours by 30 and enter that as the daily average.
Not always. The label or product page is a good starting point, but some appliances cycle on and off or use different power levels in different modes. Treat the result as a practical estimate, not a utility bill total.
Related tools
Choose the next calculator from the number you have now: watts, kWh, a one-hour check, or a full appliance-use estimate.
Home energy
What it shows
Convert appliance wattage and runtime into kWh so you can estimate energy use before working out electricity cost.
Best for
Turning an appliance label in watts into usable energy consumption over a chosen number of hours.
Home energy
What it shows
Estimate how much an appliance costs to run for one hour, a typical 8-hour stretch, or a full 24-hour day.
Best for
Getting a quick hourly running-cost estimate before checking longer daily or monthly usage.
Home energy
What it shows
Convert a known kWh amount into estimated electricity cost using your rate per kWh.
Best for
Turning known energy use from a bill, meter, appliance estimate, or watts-to-kWh result into a practical cost estimate.
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