What is rel=ugc?
rel=ugc is a value of the HTML rel attribute that marks a link as user-generated content: a link someone outside the site's editorial team posted, such as a URL in a blog comment or a forum reply. A forum that marks a member's link this way outputs:
<a href="https://member-site.example.com" rel="ugc">My site</a>The value tells search engines that the site hosting the link did not choose it editorially. Google recommends "marking user-generated content (UGC) links, such as comments and forum posts, with the ugc value" [1].
rel=ugc is one of three link qualifiers Google recognizes, with nofollow and sponsored. The nofollow link entry covers all three together. This entry goes deeper on ugc alone: which links it applies to, which platforms add it for you, and when a site might choose to remove it.
Which links should use rel=ugc?
rel=ugc applies to any link that a third party, not the site owner or its editors, can add to a page. Google's Danny Sullivan described the scope in 2019 as "pretty much any place where you allow third-party users to add links to your content" [3]. Google's link guidance says the same: if "users can insert links on your site (for example, you have a forum section or Q&A site)", mark those links ugc or nofollow [8].
Typical places rel=ugc belongs:
- Blog comments, including the commenter's website field.
- Forum posts and signatures.
- Q&A answers and community knowledge bases.
- User profiles where members can add a website link.
- Reviews and guestbooks that accept links.
- Wiki pages that anyone can edit.
The reason is spam. Google's spam policies name "forum comments with optimized links in the post or signature" as link spam [7], and treat spammy content added "through a channel intended for user content" as user-generated spam [7]. Marking these links ugc removes most of the incentive for spammers to target a site.
How does Google treat rel=ugc links?
Google treats rel=ugc as a hint, not a command. Since September 10, 2019, Google may choose to consider a ugc link for ranking, and since March 1, 2020, it may choose to crawl and index the page a ugc link points to [2][3].
Google has not published when it uses the ugc hint or how much weight it gives it. Any figure claiming to put a value on a ugc link is a guess. Google said at launch that the new values do not change "the nature of how we treat links in most cases" [3].
Which platforms add rel=ugc automatically?
WordPress is the main platform that adds rel=ugc automatically. WordPress added ugc support to comment links in version 5.3, and Ahrefs found in 2020 that WordPress sites accounted for most of the ugc use it could detect [4]. Other platforms showed little or no documented adoption at the time [4].
WordPress had already added nofollow to all user-submitted links, including comment text and the commenter's website link, since version 1.5 [2]. Adding ugc gave those links a more specific label on top of the nofollow that search engines have long recognized.
Many other blog, forum and community platforms add nofollow to user links by default, "often with no option to disable it" without changing the software's code [2]. If your platform outputs nofollow on user links, it is already compliant with Google's guidance, since nofollow remains accepted for user content [1][8]. Check a live comment or forum post (right-click the link, choose Inspect) to see what your platform actually outputs.
Should you remove rel=ugc for trusted users?
Google allows it. Google's documentation says that to "recognize and reward trustworthy contributors, you might remove this attribute from links posted by members or users who have consistently made high-quality contributions" [1].
This is the one place where ugc gives a site more room than older practice. A forum can leave ugc on links from new and anonymous accounts and drop it for long-standing members with a track record. Where the platform allows it, member groups or reputation levels are the natural place to set this.
Remove ugc only for contributors whose links you would be comfortable vouching for as your own. A followed link from a user account that later turns to spam is a followed spam link on your site.
Can you combine rel=ugc with other values?
Yes. Google accepts multiple values in one rel attribute, separated by spaces or commas [1]:
<a href="https://member-site.example.com" rel="ugc nofollow">My site</a>
<a href="https://member-site.example.com" rel="ugc,nofollow">My site</a>Two combinations are common:
ugc nofollow: a safe choice for any user link because older crawlers still see nofollow.ugc sponsored: a user-posted link that was also paid for, such as a sponsored forum post [2].
Does Bing support rel=ugc?
Yes. Bing added support for rel=ugc and rel=sponsored in 2020 and treats both as "hints, not necessarily directives" [6]. A Bing spokesperson said the new values were "not as strong of a signal for Bing" as nofollow at the time, which is another reason to pair ugc with nofollow [6]. Bing's Fabrice Canel said in 2019 that Bing had always treated nofollow itself as a hint [9].
How many websites use rel=ugc?
Very few. HTTP Archive's 2024 Web Almanac found ugc on 0.3% of mobile sites and 0.4% of desktop sites, against 32.7% and 32.4% for nofollow [5].
The low figure is easy to misread. A site with comments turned off, or a site whose platform outputs only nofollow on user links, will not show up as a ugc user even though its user links are qualified. In 2020, Ahrefs found ugc on 0.44% of referring domains and 0.016% of backlinks pointing at the top 110,000 websites, and on internal links of 3.1% of the sites it studied [4].
When did Google introduce rel=ugc?
Google introduced rel=ugc on September 10, 2019, alongside rel=sponsored [2]. It split off one of the jobs nofollow had done since 2005, when nofollow was created specifically to stop blog comment spam.
2005: nofollow is created for comments
Nofollow was introduced to stop spammers posting links in blog comments [2]. Blog software began adding it to reader-submitted links automatically, and WordPress did so from version 1.5 [2].
2019: ugc gets its own value
On September 10, 2019, Google announced rel="ugc" for "user-generated content", such as "user-contributed comments and forum posts" [2]. The same announcement turned nofollow, sponsored and ugc into hints for ranking, and Google said existing nofollow links did not need to change [3]. WordPress announced plans to convert comment links to ugc the same year [2].
2019: WordPress 5.3 adds ugc
WordPress shipped ugc on comment links in version 5.3 [4], which made it by far the largest source of the new value in the months that followed.
2020: crawling hint and Bing support
From March 1, 2020, Google extended the hint model to crawling and indexing [2]. Bing announced support for ugc in 2020, as a weaker signal than nofollow [6].
What is the difference between rel=ugc and nofollow?
rel=ugc says why a link is not an endorsement (a user posted it), while nofollow only says the site does not vouch for it. Both are hints to Google, and both satisfy Google's guidance for user-submitted links [1][8].
| rel=ugc | rel=nofollow | |
|---|---|---|
| Meaning | A user, not the site, added this link | Don't treat this link as an endorsement |
| Introduced | 2019 | 2005 |
| Accepted for user links | Yes (preferred) | Yes |
| Accepted for paid links | No, use sponsored or nofollow | Yes |
| Recognized by older crawlers | Not always | Yes |
| Can be removed for trusted users | Yes, per Google | Yes |
Do rel=ugc links help SEO?
rel=ugc links help SEO mainly through referral traffic and discovery, not through reliable ranking value. A helpful forum answer with a link sends real visitors, and since March 2020 Google may crawl a page it finds through a ugc link [2].
Posting links in comments and forums to build rankings does not work and can do harm. Google names forum comments with optimized links as link spam [7], and the hosting sites mark those links ugc or nofollow precisely so they pass nothing. Take part in communities to be useful and to be found by the people there.
What should you do about rel=ugc on your own site?
If your site accepts user content, make sure every user-submitted link carries ugc, nofollow or both [1]. In practice:
- WordPress sites: comment links are qualified by default on 5.3 and later. Inspect a live comment link to check that a theme or plugin has not stripped the attribute.
- Forums and communities: set ugc (or nofollow) as the default for member links and signatures.
- Trusted members: consider removing ugc for long-standing, high-quality contributors, as Google allows [1].
- Existing nofollow on user links: leave it. Google does not require a change [3].
- Your own editorial links: never mark them ugc. The value is only for links your users add.