SEOquake is a free browser extension produced by Semrush, and it shows: the volume of data it surfaces is impressive for a free tool. As you browse, it overlays a toolbar showing domain metrics, backlink counts, index status, and keyword density for the current page. You can also trigger a full on-page SEO audit from the extension, which checks key elements without needing to open the Semrush platform.
The SERP overlay is particularly useful during competitor research. Every result in Google gets labelled with its Semrush domain score, estimated organic traffic, backlink count, and age, giving you a detailed picture of the competitive landscape at a glance. The page comparison feature lets you open a side-by-side metric view for any two pages, which I find useful when auditing similar pages on the same site.
What I find less polished about SEOquake is the interface itself. It can feel cluttered and the amount of information visible at once takes some getting used to. Compared to the cleaner design of the Ahrefs SEO Toolbar or the Detailed extension, SEOquake has a busier feel that might overwhelm those new to SEO. The metrics are also tied to Semrush’s database, so the accuracy depends on how well Semrush has crawled the domain in question. For a free tool though, the feature set is genuinely impressive and it remains one of the most data-rich free options available.