About WattLong

WattLong is an independent calculator and reference site for backup power — built on one idea: sizing and runtime numbers should show their work.

What we do

We publish free calculators for generator sizing, power-station runtime, refrigerator and CPAP runtime, and solar charging time, backed by two datasets: power-station specifications taken from manufacturer product pages and manuals, and an appliance wattage table sourced from Generac's official sizing publications and Home Depot's sizing guide.

How we're different, in verifiable ways

• Sources on the page. Every model page names where its specs came from and when they were pulled. Every appliance row names its source.
• Conflicts shown, not smoothed. When manufacturers or sizing guides disagree, we publish the range and the disagreement — we never average two sources into a number neither of them printed.
• Uncertainty labeled. Assumptions carry grades (CONFIRMED / REPORTED / INFERRED) on our methodology page.
• Refusals included. If a power station can't start your load, our calculators say so instead of printing a runtime. If your appliance list outgrows every battery we list, the sizing tool says that too.
• Corrections in public. Fixed errors are recorded on the corrections log with dates.

What we are not

WattLong is not affiliated with EcoFlow, Bluetti, Jackery, Anker, Goal Zero, Generac, or any other manufacturer named here, and we don't sell power stations directly. We are not electricians and don't give electrical or medical advice.

Spot an error? Tell us — data corrections are the most useful mail we get.