How the ranking works

A ranking is only worth sharing if it is fair. Every site on CrashedLink is measured with exactly the same crawl, the same rules and the same formula. Paying for a report never changes a public score.

1. The same crawl for everyone

  • We open the homepage and follow internal links two levels deep.
  • At most 100 pages and 1,500 unique links discovered. Usually about two minutes; up to four when a site starts rate-limiting us and we slow down to stay polite.
  • We verify every external link and up to 300 internal links beyond the pages we already read, prioritised by prominence (navigation first, then homepage, then the most-linked URLs). Anything past that cap is left unchecked and excluded from the score.
  • We respect robots.txt and pace ourselves to about five requests per second per host, two at a time. Faster than that and bot walls start answering for the site.
  • Each site is scanned at most once every 7 days.

This measures the part of a site visitors actually see. Deep archives are covered by the full report, not by the ranking.

2. What counts as broken

  • Broken: HTTP 404 or 410, confirmed by a second request with a browser user agent.
  • Unverifiable: timeouts, network errors, 401/403/405/429, bot walls (Cloudflare and similar) and hosts known to block crawlers such as Facebook, Instagram, LinkedIn, X, TikTok, YouTube and Amazon. These are shown but never counted.
  • Error: 5xx responses. Reported separately because they are usually transient.
  • A URL is counted once, however many pages link to it.
  • Pending: some sites answer 404 for their own pages while they are throttling a crawler. When a site rate-limited us during the scan, or three or more of its navigation links came back 404, those links are held as pending, left out of the score, and re-checked one by one about ten minutes later. Only what is still 404 then counts. Pages show a “verifying” badge in the meantime.

3. The Link Health Score

Each broken link gets a weight from where it lives: navigation, header or footer = 3, homepage = 2, any other page = 1. Internal links (pointing to the same site) count double, because they are fully under the site's control.

rate  = weighted broken links / verified links × 1,000
score = 100 − rate   (clamped to 0…100)

A ≥ 90 · B ≥ 75 · C ≥ 60 · D ≥ 40 · F < 40

Sites need at least 30 verified links to appear in the ranking; below 100 we flag the score as a small sample, because one broken link moves it a lot. Ranking position is by score, lowest first; ties are broken by the raw number of broken links.

4. AI-agent readiness

Since May 2026 Lighthouse reports an Agentic Browsing category. We run the cheap parts of it on the homepage: a valid llms.txt at the root, structured data (JSON-LD), and semantic landmarks with a language attribute. It is informational and does not affect the Link Health Score.

5. Corrections

If you believe a site was scored incorrectly, rescan it after the 7-day window or write to the address in the footer with the domain and the URLs in question. We publish the rules so that anyone can check them.