Indexing

Indexing is the process where a search engine takes a page into its index, the database of every page that can appear in the search results. A page that is not indexed does not exist in Google, however good it is, which makes indexing the most basic precondition in all SEO work.

The route into the index has three steps. First Googlebot crawls the page, finding the URL through links or through your sitemap and fetching the HTML. Then Google renders the page, so JavaScript runs and the page looks the way visitors meet it. Last, Google decides whether the page belongs in the index at all.

The chain can break at any of the three. A page blocked in robots.txt is never crawled. Content that only appears after heavy JavaScript can stall in rendering. Thin or duplicated pages are often crawled without ever being taken in, the status Google Search Console reports as "Crawled, currently not indexed". Indexing is a judgment Google makes page by page, not a right that follows from publishing.

The index also feeds more than the blue links. AI Overviews and Google's AI Mode draw their sources from the same index, so a page missing from it is invisible in AI answers too. The full chain from discovery to indexed page belongs to the guide on crawling and indexing.