Noindex is a meta robots directive that explicitly requests that a page not be indexed by a search engine. It is generally implemented in two ways:
<!-- inside HTML head -->
<meta name="robots" content="noindex">
<!-- in HTTP response header -->
X-Robots-Tag: noindex
For the noindex directive to work, the bot must be able to crawl the page. In other words, adding noindex to a page blocked by robots.txt is meaningless — the bot will not crawl the page and cannot see the tag.
Types of pages that should use noindex:
- Site search results pages
- Most tag pages (if they do not provide real value)
- Author archive pages
- Filter/sort parameters
- User-specific pages such as login, registration, account, and cart
- Thank-you pages (after form submission)
- Test environments or development pages
- Low-quality or insufficient content (improve it first; if that is not possible, use noindex)
Common mistakes:
- Using robots.txt + noindex at the same time (the bot cannot see the tag)
- Accidentally leaving important pages as noindex (common when moving from development to production)
Tip: Regularly check the “Pages > Excluded by noindex tag” report in Search Console. If a page you want indexed appears there, fix it immediately.