What is the difference between crawling and indexing?
Technical SEO
Crawling vs Indexing are distinct stages in how search engines like Google discover and serve content:
Crawling: the process whereby search engine bots (crawlers) discover web pages by following links, reading sitemaps, or being told via robots.txt.
Indexing: once a crawler accesses a page, the content is evaluated (quality, relevance, content, signals), and if acceptable, stored in the search engine’s index so it can appear in search results.
Why this matters in 2025: with large scale AI content, more pages may be crawled but filtered out before indexing due to quality / duplication issues.
Further reading:
https://www.outrank.so/blog/how-to-fix-crawled-but-not-indexed