What is a noindex tag?
The noindex directive is an instruction to search engine crawlers not to include a page in their index. It is implemented as a robots meta tag in the page's <head> (<meta name="robots" content="noindex">) or as an HTTP response header (X-Robots-Tag: noindex).
When to use noindex
Noindex does not prevent crawling — Googlebot will still visit and re-read the page to check whether the directive has been removed. To prevent crawling entirely, use robots.txt. To prevent indexing of a page that should not appear in search results, use noindex. The two signals serve different purposes and are often confused.
Noindex is appropriate for: admin and login pages, thank-you pages (post-form submission), filtered or faceted navigation combinations, printer-friendly versions, staging environments, and pages with thin or duplicate content that would otherwise dilute site quality signals.
Example
Example
A common migration error: a site's staging environment had noindex on every page, which was never removed after launch. All 600 pages passed technical checks (crawlable, no 404s) but none appeared in search results. The issue only surfaced in Google Search Console's Coverage report three weeks post-launch.
Frequently asked questions
Why is my noindexed page still in Google?
Google must crawl the page to see the directive. If the URL is also blocked in robots.txt, the noindex is never read and the page can linger in the index. Allow crawling, let Google process the tag, then block if needed.
Does noindex stop Google from crawling a page?
No. Googlebot keeps revisiting to check whether the directive changed, though frequency drops over time. To prevent crawling itself, use robots.txt; the two controls solve different problems.