GeneratorCalc
Simple calculators for backup power & energy use
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Quick summary

This helper gives a rough suggestion for extension cord gauge when you are running loads from a portable generator.

Enter load amps and cord length to see a suggested wire gauge based on common rules of thumb for 120V circuits.

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

Extension cord gauge helper for generator loads

Use this helper to get a rough idea of what extension cord gauge might be appropriate for a given load and cord length.

Always follow the cord manufacturer’s ratings and local electrical code; this tool is for simple planning only.

Extension cord gauge helper

Estimate a suitable extension cord gauge based on load amps and cord length.

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

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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.

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