What this free SEO tool checks
Paste any URL and the analyser fetches that single page and reads it the way a crawler does: the response status and redirect chain, the canonical and robots directives, the title and meta description, the heading outline, every image and its alt text, and the internal and external links on the page.
Everything comes from one fetch of one page. That is the whole reason it is free and instant — there is no queue, no crawl budget and no account, because the work is a single request rather than a site-wide crawl.
