GeneratorCalc
Simple calculators for backup power & energy use
Free tools • No signup • No data saved

Quick summary

This calculator turns generator watts and run time into kilowatt-hours (kWh), the same unit your electric bill uses.

Enter generator watts, load percentage, and hours of run time to estimate energy output.

GeneratorCalc
Simple calculators & guides for backup power
Free tools • No signup • No data saved

Generator kilowatt-hour (kWh) output calculator

Use this calculator to estimate how many kilowatt-hours your generator produces over a period of time.

It is helpful when you want to compare generator energy use and cost against your normal utility power.

Generator kWh output

Estimate energy in kilowatt-hours (kWh) based on load and hours of run time.

For more planning tools, you can also use the other calculators and guides on the GeneratorCalc home page.

You might also find these helpful:

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These tools are for planning and estimation only. They do not replace manufacturer specifications, local codes, or professional advice. Always follow your generator manual and consult a qualified professional for permanent installations or whole-home backup systems.

GeneratorCalc is reader-supported. As an Amazon Associate, we earn from qualifying purchases made through links on this site.

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