How we work

Test

Runtimes are measured, not quoted

A capacity claim on this site is either measured or labeled as the manufacturer's. When a page carries the tested badge, we bought the unit, plugged it into a metered real load — a refrigerator, a CPAP, a router, the things an outage actually threatens — and timed it until it shut down. Spec-sheet watt-hours assume 100% depth of discharge and a perfect inverter; our numbers include the losses, which is why they're lower and why they're useful.

Where we haven't tested a unit yet, the page says so, the numbers are attributed to their source, and the math is shown so you can check it.

Source

Every claim carries a citation with a date

Every factual claim — a price, a spec, a commission-relevant detail — is backed by a source you can see in the ledger at the bottom of each page, with the date we last checked it. Citations older than 120 days fail our build: the page cannot ship until the claim is re-verified or removed. Prices and promos in this niche move fast; a dated citation is the difference between information and rumor.

Money

Affiliate links never touch the rankings

This site earns commissions from some links — every one of them is marked, routed through a visible /go/ redirect, and tagged rel="sponsored". Picks and rankings are decided on the math first; the links get attached afterward. No brand sees a draft, buys a placement, or edits a verdict. If a recommendation ever changes because the commission changed, that would be a correction-level failure — see the next section.

Correct

Substantive changes are logged in public

When a claim changes after publish — a corrected spec, a re-tested runtime, a retracted recommendation — the change is logged on the corrections page with a date and what changed. Typo fixes don't get entries; anything that could have changed your buying decision does.