Amazon hides Best Sellers Rank on search results, so you open listing after listing to see what sells. BSR Overlay puts the rank on each result card, colour-coded by thresholds you set. It loads ranks only for the cards you can see, and caches them, so scrolling back is instant. You choose how many requests run at once. One declared permission: storage, for your settings. It runs only on Amazon marketplace pages. No server, no analytics, no account. 21 marketplaces.