Generator Size Calculator

Motors and compressors need a surge of power to start. Pick the appliances you'll run and get both running and starting watts — then find the generator that handles them.

⚡ Surge aware

Refrigerators and ACs spike to 2-3x running watts on startup — the calculator includes those peaks.

🚚 Right size, not max

Oversized generators waste fuel and never load properly. Buy for your actual needs plus margin.

🏠 Whole-home plan

Switch between portable essentials and whole-house standby scenarios to compare.

🔒 Private

All calculations run locally in your browser.

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