Power Cost Calculator
Calculate daily, monthly and yearly energy use and cost from power, usage time and electricity price.
What this tool does
Estimate energy use and cost from device power, hours per day, period and price per kWh. Enter average real power rather than the maximum printed on a power supply; the result excludes taxes or standing charges unless you include them in your tariff.
How to use it
Enter the values requested by the calculator and check the result together with the notes shown below it.
Practical example
Use a realistic example from your own setup to compare scenarios. The result is a reference, not a replacement for manufacturer specifications.
How to interpret the result
Treat the result as an estimate whenever real-world factors are not available to the browser. For hardware, network or safety decisions, verify the relevant technical specifications.
Frequently asked questions
How is the cost calculated?
Power is converted to kWh by multiplying by the hours of use, and that consumption is multiplied by the kWh price you enter.
Which wattage should I enter?
The device’s real power draw in use, not the maximum rating of its power supply. A plug-in power meter gives the most reliable figure.