Nofollow and crawling
rel=nofollow tells search engines you do not vouch for a link. Since 2019 Google treats nofollow (and the related sponsored and ugc values) as hints rather than strict directives for crawling and indexing. This page explains the link attributes, why nofollow is not a reliable way to control crawling, and how it differs from robots.txt and noindex.
What this means
rel=nofollow on a link tells search engines you do not vouch for the destination. Originally it asked crawlers not to follow the link or pass signals. In September 2019, Google changed nofollow to a hint for crawling and indexing purposes — Google may still choose to crawl the linked URL.
Google also introduced two more specific values: rel=sponsored for paid or advertising links, and rel=ugc for user-generated content links. You can combine values (for example nofollow ugc).
The link relationship values
Use rel=sponsored for advertisements, paid placements, and affiliate links. Use rel=ugc for links in user-generated content like comments and forum posts. Use rel=nofollow for other cases where you do not want to endorse a link but none of the more specific values fits.
All three are treated as hints for crawling and indexing. They are signals about the nature of the link, helping Google decide whether and how to use it, rather than hard commands.
- rel=sponsored — paid/advertising/affiliate links
- rel=ugc — user-generated content links
- rel=nofollow — general no-endorsement links
- All treated as hints since 2019; values can be combined
Why nofollow is not crawl control
Because nofollow is a hint, it cannot reliably prevent a URL from being crawled or discovered — Google may follow the link anyway, and the URL can also be discovered through other links or sitemaps. So do not use nofollow to keep a page out of the index.
To prevent crawling, use robots.txt (which stops compliant crawlers from fetching). To prevent indexing, use a noindex meta tag or header on a crawlable page. nofollow addresses endorsement and link relationships, not crawl or index control — pick the right tool for the goal.
How it appears in analytics and logs
A nofollow link signals that you do not endorse the target. Since 2019, Google treats it as a hint for crawling and indexing, meaning it may still crawl a nofollowed URL. So nofollow is not a reliable crawl block; it is an endorsement and link-relationship signal.
Diagnostic use case
Use the correct link relationship for sponsored, user-generated, or untrusted links, and understand why nofollow is not a dependable mechanism to stop a URL from being crawled or discovered.
What WebmasterID can help detect
WebmasterID shows which URLs crawlers actually fetch, so you can observe that a nofollowed URL may still be crawled (because nofollow is a hint), helping you avoid relying on nofollow for crawl control.
Common mistakes
- Relying on nofollow to stop a URL from being crawled — it is only a hint.
- Using nofollow to keep a page out of the index instead of noindex.
- Using generic nofollow for ads or UGC instead of the specific sponsored/ugc values.
- Assuming nofollow links never pass any signal after the 2019 hint change.
Privacy and accuracy notes
Link relationship attributes describe links, not visitors. WebmasterID records crawler fetches of linked URLs as bot events and stores no user data.
Frequently asked questions
- Does nofollow stop Google from crawling a link?
- Not reliably. Since 2019, Google treats nofollow as a hint for crawling and indexing, so it may still crawl a nofollowed URL. Use robots.txt to prevent crawling and noindex to prevent indexing.
- When should I use sponsored or ugc instead of nofollow?
- Use rel=sponsored for paid, advertising, or affiliate links and rel=ugc for user-generated content links like comments. Use plain rel=nofollow when neither specific value applies. You can combine values where appropriate.
Related pages
- Internal linking for crawl discovery
Internal links are how crawlers discover and reach pages within a site. Google primarily finds new URLs by following links, so pages with no incoming internal links become orphans that are hard to discover. This page explains crawl depth, link equity flow, and practical patterns — hub pages, breadcrumbs, related links, and crawlable HTML anchors — that keep important pages within easy reach of a crawl.
- Fixing 'Indexed, though blocked by robots.txt'
A URL disallowed in robots.txt can still appear in Google's index if other pages link to it — Google may index the URL (often with no useful snippet) without crawling it. The trap is that a noindex tag on that page cannot be seen, because robots.txt stops Google fetching the page to read the tag. The fix is to allow crawling and use noindex, or to remove the link signals.
- Noindex but heavily linked: a diagnosis
A noindex page that is still prominently linked across the site is a common, subtle conflict: you are telling search engines not to index a page while structurally treating it as important. Either the noindex is a mistake on a page you want indexed, or the heavy linking wastes internal link equity on a page you have chosen to keep out of the index. Diagnosis is about resolving the contradiction.
- Bot intelligence
See which URLs crawlers fetch, including links you marked nofollow.
Sources and verification notes
- Google Search Central — Qualify outbound links (nofollow, sponsored, ugc)Link attributes and the hint behavior.
- Google Search Central Blog — Evolving nofollow
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.