How we compare power stations

WattSheet is a spec sheet and a calculator, not a test lab. We collect each maker's published numbers, re-check them on a schedule, run the same math for every model and rank by the result.

What is listed

25 portable power stations from EcoFlow, Jackery, Bluetti and Anker. A model is added once it is widely on sale in the US and its specs and price can be confirmed, and removed when it is discontinued. This is not every power station on the market.

Where specs come from

Capacity, output, weight, charging and battery figures are the maker's published numbers. Each station page links to the maker and shows the date its specs were last verified; a few stations are re-checked every day, oldest first. Where a maker does not publish a figure, the page says "not published" instead of guessing.

Prices

For stations sold in the brand's own US store, price and stock are read from that store every day. For the rest we show a typical sale price checked by hand. Each station page says which applies and the date it was checked. Prices move often, so confirm at the retailer.

Runtime estimates

Runtimes use the same math as the calculator: capacity times 85% inverter efficiency, divided by the device's average draw. A station counts as able to run a device only when its continuous output covers the device's running watts and its surge rating covers the start-up watts. Device wattages are typical values, shown on each page; yours may differ. These are estimates, not lab tests.

Accessories

Solar panels and add-on batteries are listed next to a station only where the maker states the pairing: either it sells the station with that accessory as a kit, or the accessory's listing names the station. Each accessory page quotes that statement, links to it and shows the date we last found it there; a script re-checks every pairing daily. Solar refill times are our estimate (capacity divided by 75% of the panel's rated watts, capped at the station's solar input), not a test.

Rankings

Every "best" pick is computed. Best value is the lowest price per watt-hour. Use pages, such as refrigerators or CPAP machines, rank the stations that can run the device by runtime and price. Head-to-head verdicts compare the two models' numbers line by line.

What we do not do

• We do not test products hands-on, and nothing on this site is presented as a test result.
• We do not accept payment for placement, and commission rates are never an input to a ranking.
• We do not publish user reviews or star ratings.

Corrections

If a number on this site is wrong or out of date, tell us at corrections@buyersheet.com and we will check it against the source.

How the site earns money

Some links to retailers are affiliate links, which can pay us a commission when you buy, at no extra cost to you. Details are in the affiliate disclosure.