Indexability

Indexability refers to a search engine's ability to analyze a page and store it in its index, the database from which it draws search results. A page must be both crawlable, meaning the engine can access it, and free of directives that block indexing for it to be indexable.

Indexability is distinct from crawlability. A crawlable page can still be excluded from the index by a noindex tag, a canonical pointing elsewhere, or quality issues. Only indexable pages are eligible to rank.

Several factors determine whether a page gets indexed. Technical blockers include noindex tags, robots.txt rules preventing the crawl, canonical tags pointing to another URL, and server errors. Quality factors also matter: thin, duplicate, or low-value pages may be crawled but left out of the index.

Google's index coverage report shows which pages are indexed and why others are excluded, making it the primary tool for diagnosing indexability problems across a site.

Ensure important pages are crawlable, free of unintended noindex tags, and not canonicalized to other URLs. Submit a clean XML sitemap, fix server errors, and resolve redirect chains that interfere with crawling.

Quality is equally important. Pages excluded as thin or duplicate need improvement or consolidation rather than technical fixes. Strong internal linking also helps, since well-linked pages are discovered and indexed more reliably than orphan pages.