As-is, and free
Gen Sizer is a free tool, provided as it is — no account, no fee, no warranty. We keep the right to fix it, improve it, change it, or retire it.
Guidance, not guarantees
The kilowatt verdict Gen Sizer returns is a planning estimate built on a stated method: your checked appliances' typical running watts, a 20% margin, the startup peak of the single largest motor kick added over the rest, and a round-up to the nearest size actually sold. Those are sizing conventions from published generator guides, not measurements of your specific appliances or generator — model, age, and nameplate all move the needle. Treat every verdict as a well-founded starting point.
The data, with its caveats
The appliance wattage table is compiled from public reference sources — ENERGY STAR criteria, U.S. DOE / Oak Ridge National Laboratory energy data, manufacturer specifications (including Goulds/Franklin well-pump, Pentair/Jandy pool-pump, Wayne/Flotec sump-pump, and ResMed/Philips CPAP data), nameplate EER math for window ACs, and the portable/standby sizing conventions published by Generac and Briggs & Stratton. Every value is a typical mid-range pick from those sources. Actual appliances vary; the source data may change; this is reference data, not an engineering specification for your home.
Your judgment — and your electrician's — have the final word
Put nameplate amps × volts on anything mission-critical, and remember this is a sizing sanity-check, not a substitute for the electrical code. Transfer switches, panel hookups, feeder sizes, permits, and whole-home standby installs are a licensed electrician's decisions, and their call governs. Nothing on this site is engineering, electrical-code, or safety advice.
The name and the work
The tool's name is Gen Sizer — two words, no hyphen. The name, the writing, and the code on this site belong to Kodiak Foundry LLC. Link to the tool freely; don't republish its content as your own.
The law
These terms fall under the law of the State of Florida. If this page changes, the date below changes.
Contact
© 2026 Kodiak Foundry LLC — Florida, USA
Terms last updated: November 12, 2026