Defective Links

A defective link is any hyperlink that fails to deliver a visitor to a working destination — it may return a 404, point to a page that was moved or deleted, contain a typo in the URL, or loop through a chain of redirects. To a user it's a dead end; to a crawler it's a wasted request.

Common causes

• A target page was deleted or renamed without a redirect
• A typo or broken relative path in the HTML, such as a missing slash
• An external site you linked to reorganized its URLs or went offline
• Redirect chains and loops that never resolve to a final page
• An HTTPS migration that left old HTTP links or mixed-content references

Why they hurt more than they look

Defective links quietly damage three things: user trust, because people bounce when they hit a dead end; crawl efficiency, because bots spend budget on URLs that go nowhere instead of your real pages; and link equity, because a backlink pointing at a 404 passes no value. On a large site, a few hundred defective internal links can strand otherwise strong pages. They're closely related to ordinary broken links, but the category also covers malformed and looping URLs.

Finding and fixing them

A publisher migrates its blog and 320 old article URLs start returning 404s — but 40 of them still have backlinks from news sites. An SEO audit crawl surfaces them, and the team 301-redirects each old URL to its closest live equivalent. The reclaimed links restore rankings on the migrated posts within weeks, and overall crawl waste drops sharply.