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

Quick summary

This calculator estimates how many gallons of fuel per hour a small portable generator might use at a given load.

Enter generator watt rating, load percentage, tank size, and fuel type to estimate hourly use and approximate runtime.

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

Generator fuel consumption and runtime calculator

Use this calculator to get a rough idea of how much fuel your generator might burn each hour at a given load.

It is based on common fuel burn patterns for small portable generators and is meant for planning, not a substitute for your model’s official specifications.

Generator fuel use and runtime

Estimate gallons per hour and how long your fuel tank might last at a given load.

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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