Indexing is the process by which a search engine adds a page to its searchable database after crawling it. A page must be indexed before it can rank for any query — and indexing is no longer guaranteed for low-quality content.
Modern Google indexing is selective: the bot crawls billions of pages it never indexes. The decision depends on perceived content quality, link signals, schema, page speed, and uniqueness. Pages can be 'crawled, currently not indexed' for months or permanently.
Check indexing via Google Search Console's URL Inspection tool, the `site:` operator (rough but cheap), and the `Coverage` report. Bing publishes similar data via Bing Webmaster Tools.
If a page is not indexed, no SEO work on that page matters. Indexation rate (indexed pages / submitted pages) is a leading indicator of overall content quality and a critical health metric for content-heavy sites.
See it in the product: Indexation tracking.