Two minutes. Real appliance draw numbers. Specific product names — not a watt-hour range that leaves you guessing.
What it does
Calculates your real watt-hour requirement from actual appliance draw — not nameplate ratings.
Surge warnings
Flags sump pumps, well pumps, and AC units that will trip an undersized inverter.
Real recommendations
Returns specific model names by tier — not a generic capacity range.
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This changes everything. A mountain hunter and a homeowner need very different systems.
Select everything you want to keep running. You can start small and expand later.
Choose the outage duration you want to plan for. Going longer gives more protection but costs more upfront.
Select your primary use case — home backup, medical devices, camping, RV, or off-grid. Each changes which appliances appear and how we model your duration needs.
Choose which devices need to run and for how long. The watt figures are real measured draw numbers, not nameplate ratings — nameplate ratings are almost always higher than actual consumption.
You get your minimum watt-hour requirement with a built-in 25% buffer for inverter losses. Surge warnings appear automatically for sump pumps, well pumps, and large motor loads. Products are named by tier.
No calculator replaces reading the actual spec sheet for your specific appliance. Wattage varies widely by model and age. If your application is critical — medical life support, sump pump in a flood-prone basement — verify numbers against your actual equipment before buying.
Well pumps above 1 HP and central air conditioning units generally exceed portable power station limits. The calculator flags these automatically but confirm with your equipment documentation.
Browse guides organised by your specific situation — sump pumps, medical devices, camping, RV, and more.
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