What Is Nofollow?

The rel="nofollow" attribute sits inside the <a> tag, next to the destination URL, telling Google not to treat that link as an editorial vote of confidence. Nothing changes for visitors: a nofollow link stays visible and clickable, the only difference is how Google's crawlers process it. Technically, it's just a text value inside the rel attribute, not a separate line of code or its own HTML element.

The value was proposed in January 2005. Google, Yahoo and MSN Search adopted it together as a countermeasure against comment spam, which at the time filled any open comment box with unrelated promotional links.

For more than a decade, nofollow was the only way to mark a link as "I don't vouch for this destination." There was no gradation between a paid link, an anonymous forum post, or a link to a dubious site, in contrast to today's default behavior, known as a dofollow link. That missing granularity became a growing problem as paid partnerships and user-generated content spread across the web, and it's exactly what the 2019 reform set out to fix.

The three values can be combined on a single link, for instance rel="nofollow sponsored" on an ad banner that also points to an unverified external domain. Google recommends using the most specific attribute available: sponsored and ugc give more context than a generic nofollow, even though all three have shared the same underlying treatment since 2019.

<!-- No rel: dofollow, the default behavior -->
<a href="https://zds.es/en/what-is-dofollow/">normal internal link</a>

<!-- rel="nofollow": no editorial endorsement, unverified destination -->
<a href="https://example.com" rel="nofollow">unverified external link</a>

<!-- rel="sponsored": paid or affiliate link -->
<a href="https://example.com" rel="sponsored">sponsored link</a>

<!-- rel="ugc": user-generated content -->
<a href="https://example.com" rel="ugc">user comment</a>

Before 2019, rel="nofollow" was a strict instruction: Google didn't count the link toward PageRank calculations and passed no ranking value at all, no exceptions. It was effectively a binary rule, with no room for degrees, regardless of how trustworthy the linked page actually was.

On September 10, 2019, Google announced it was changing that behavior from the ground up. Since March 1, 2020, nofollow, sponsored and ugc are treated as a hint rather than a mandatory directive. Google can still choose not to pass ranking value through those links, but it's no longer required to ignore them outright: the hint gets combined with other signals when deciding whether to crawl, index or weigh the link.

The practical difference matters: under the old rule, a nofollow link was guaranteed to pass no value whatsoever. That guarantee is gone. If other signals suggest the link is worth following, Google can still crawl the destination page, something that never happened under the old rule. This is the part most often misunderstood: nofollow is no longer a lock, it's a recommendation Google can accept or ignore. In practice, nobody can promise with total certainty anymore that a link marked nofollow will carry zero weight in how the destination page ranks.

Nofollow makes sense in three concrete situations. For paid or affiliate links, where rel="sponsored" is the correct choice instead of a generic nofollow, particularly relevant in cross-selling campaigns built on affiliate marketing links. For user-generated content, where ugc applies. And for links to destinations the site doesn't control or want to vouch for editorially.

There's also a compliance reason: promoting paid links without marking them accordingly breaks Google's guidelines around technical SEO and can be treated as a manipulative link scheme, with the risk of a manual penalty that can hit the entire domain, not just the individual link.

A link carrying none of these three attributes is, in SEO jargon, a dofollow link, the default state of any link in HTML. Whether or not to mark a link nofollow is, at its core, a decision about which destinations a site is willing to vouch for, one best made while writing the content rather than fixed later during a technical review.

• Use rel="sponsored" for paid or affiliate links, and reserve generic nofollow for other cases.
• Use rel="ugc" on comments, forums, and any link added by users without editorial review.
• Combine values where it makes sense, for instance rel="nofollow sponsored" on an unverified external ad banner.
• Don't use nofollow as a substitute for noindex or a robots.txt rule to hide your own content: they're different mechanisms with different effects.
• Check your comment plugin's default setting: some apply nofollow to every outbound link regardless of content type.
• Remember that since 2020 nofollow is a hint, not a guarantee: don't assume a nofollow link will never be crawled.

• Thinking nofollow hides the link from visitors: it only changes how Google treats it, the link stays fully visible and clickable.
• Marking paid links with generic nofollow instead of sponsored, which doesn't fully meet Google's guidelines on paid links.
• Assuming nofollow guarantees, with total certainty, that Google will never crawl or index that URL, which stopped being true in 2020.
• Confusing nofollow with robots.txt or the noindex meta tag, which are independent mechanisms with different functions.
• Never checking what the comment plugin sets by default, then discovering months later that every outbound link on the blog carries an unnecessary nofollow.