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Calculators / Everyday / Electricity cost
Electricity cost calculator
Calculate the cost of a known kWh amount or estimate appliance energy cost by day, month, and year.
On this page
Cost for entered energy13.5USD
Energy for entered period90kWh
Estimated daily cost13.5USD
Estimated monthly cost13.5USD
Estimated annual cost13.5USD
Calculator controls
How to calculate
Calculate the cost of a known kWh amount or estimate appliance energy cost by day, month, and year.
Cost = energy in kWh × price per kWh. Appliance energy = watts ÷ 1,000 × hours × days.
Worked example
Input method: energy; Energy use: 90; Energy period: single; Appliance power (watts): 1500; Hours used / day: 2; Days in entered period: 30; Cost per kWh: 0.15; Currency: USD.
Cost for entered energy: 13.5 USD; Energy for entered period: 90 kWh; Estimated daily cost: 13.5 USD; Estimated monthly cost: 13.5 USD; Estimated annual cost: 13.5 USD.
Assumptions and limits
Excludes standing charges, taxes, tiered tariffs, demand charges, and changing appliance power.
Results are rounded for display; calculations use unrounded values. Read our calculation methodology.
Understanding the result
Energy use converts rated power and operating hours into kilowatt-hours. Cost applies a single price per kWh to that energy.
When this tool is useful
Estimate the running cost of an appliance over a stated number of days.
Understanding your inputs
| Input | What to enter |
|---|---|
| Input method | Enter one of the available options. |
| Energy use | Enter a number of at least 0 and no more than 1000000000000. |
| Energy period | Enter one of the available options. |
| Appliance power (watts) | Enter a number of at least 0 and no more than 1000000000000. |
| Hours used / day | Enter a number of at least 0 and no more than 24. |
| Days in entered period | Enter a number of at least 1 and no more than 3660. |
| Cost per kWh | Enter a number of at least 0 and no more than 1000000000000. |
| Currency | Enter one of the available options. |
Frequently asked questions
Why is actual electricity use different?
Many appliances cycle on and off or vary their power. Use average consumption where known, rather than assuming maximum rated power continuously.
Does this include standing charges?
No. Fixed charges, tiered rates, and time-of-use tariffs are excluded.