What is Indexing?
Indexing is the process search engines use to store and organise content after it has been discovered through crawling. When a page is indexed, it becomes eligible to appear in search results for relevant queries.
Think of the index as a massive library. When a crawler finds a page and determines it’s worth saving, that page is added to the search engine’s index — a database of all the content Google or another search engine knows about.
Why Indexing Matters
If a page isn’t indexed, it won’t appear in search results at all, no matter how relevant or useful the content might be. That’s why indexing is one of the most important steps in SEO. Making sure your pages are crawlable, accessible, and meet quality standards increases the likelihood of being indexed.
Several factors can influence whether a page is indexed, including:
- Robots.txt settings or meta tags that block indexing
- Duplicate or thin content that lacks value
- Server errors or broken links
- Poor site structure or missing internal links
- Canonical tags pointing elsewhere
Monitoring which pages are indexed helps you track which parts of your site are visible in search and identify issues that could be holding content back.
Example in Use
You add a new product page to your website. Once a search engine crawler discovers it, the page is evaluated and, if it meets quality criteria, added to the index. After indexing, the page can appear in search results when someone searches for related keywords.
You can check the indexing status of your pages using tools like Google Search Console, which shows which URLs have been successfully indexed and which have not.