Free energy calculator
Appliance Electricity Cost Calculator
Estimate the cost of operating an appliance over a chosen number of days. Use your own bill rate for a decision-relevant result.
Calculate your estimate
Change the example values to match your system.
Estimated result
Energy used—
Estimated cost—
Enter valid inputs and calculate to see results.
These are estimates, not guaranteed performance.
Formula and method
Energy (kWh) = watts × hours per day × days ÷ 1,000. Cost = energy × price per kWh.
Displayed results are rounded to two decimal places.
What the inputs mean
- Appliance power (W)
- Enter appliance power in W.
- Use per day (hours)
- Enter use per day in hours.
- Number of days (days)
- Enter number of days in days.
- Electricity price ($ / kWh)
- Enter electricity price in $ / kWh.
Worked example
A 1,000 W appliance used 2 hours daily for 30 days consumes 60 kWh and costs $9.60 at $0.16/kWh.
Why the real result may differ
- Actual power can differ from the nameplate rating when an appliance cycles or changes operating modes.
- Taxes, fixed charges, time-of-use pricing, and tiered rates are not modeled; use a bill-derived rate when possible.
Common mistakes
- Do not confuse watts (power) with watt-hours or kilowatt-hours (energy).
- Use the appliance’s average operating power or duty cycle when it does not draw its rated power continuously.
Frequently asked questions
Why may my utility bill differ?
This arithmetic estimate uses one energy rate. Utility taxes, fixed fees, time-of-use periods, and tiered prices may change the billed amount.
Related tools
References
Last reviewed: August 12, 2026