A crawler follows links, fetches pages and reads their markup. Everything an audit tool knows about a site starts here, which is why a site that blocks crawlers is unmeasurable rather than healthy.
Ours identifies itself as Rankelle-Audit, obeys robots.txt, rate-limits per host, and discards page text after hashing the fields that matter.
Try it on your own site, free
No card, and the free tier does not expire — the first verdict takes about six weeks to arrive.