Blog comment links carry ugc or nofollow and are built to pass no ranking credit. What Google has said, how to check one, and when a comment is worth it.
Blog comment links are not a ranking tactic, so stop counting them as link building. Comment links are meant to carry ugc or nofollow, and Google said in 2019 that it would generally "not consider them for ranking purposes". A comment can still earn you something else: a reader who clicks through, or an editor who remembers your name. Here is what Google has said, including about spam comment links pointing at you, how to check a comment link yourself, and how to pick blogs where a comment is worth writing.
Why comment links pass little or no credit
Comment links are where nofollow started. In January 2005 Google's post on preventing comment spam introduced the attribute and said links carrying it "won't get any credit when we rank websites in our search results." Google asked sites and blog software makers to add it "anywhere that users can add links by themselves, including within comments, trackbacks, and referrer lists", and WordPress, Blogger and LiveJournal were among the first to sign on.
Google now has a value for user-generated links like these. Its guide to qualifying outbound links says: "We recommend marking user-generated content (UGC) links, such as comments and forum posts, with the ugc value." It also says that when it crawls, links marked sponsored, ugc or nofollow "will generally not be followed."
In September 2019 Google changed these values into hints rather than strict rules. That sounds like an opening, but Google added: "In most cases, the move to a hint model won't change the nature of how we treat such links." Plan as if a comment link passes nothing.
Can comment links hurt you?
A ugc link on its own does not get the linked page dropped from Google's index. Asked in Google's November 2022 office hours whether moderated blog comment pages internally linked with ugc get deindexed, John Mueller said no: a ugc link is treated differently, but "this doesn't negatively affect the destination page".
Comment spam is another matter. Google's spam policies list "Forum comments with optimized links in the post or signature" and "Using automated programs or services to create links to your site" as link spam, and the same page says sites that violate the policies "may rank lower in results or not appear in results at all." A keyword in place of your name, a signature link or a tool that posts comments for you all match those examples.
Spam comment links pointing at your site are not a threat either, according to Google's John Mueller. A site owner asked him about spam comments on an old post on another site, linking to their site with adult anchor text. They had already emailed the blog owner and disavowed the links. Mueller's reply on Bluesky in January 2026, as Search Engine Roundtable reported, was that these links come from spammers dropping links into comments and "would not have any effect, positive nor negative, on your site." Barry Schwartz of SER reads the reply as also covering spam links left in your own comments section. So there is no need to chase spam comment links pointing at you. If spam fills your own comments, remove it for your readers.
How to check a comment link yourself
Before you spend time on a site's comments, look at what it does with the links.
- Open a post with a few approved comments and right-click a commenter's name. Choose Inspect.
- Read the
relvalue on the link.ugc,nofollowor both means the site is qualifying the link, and Google treats it as a hint rather than a normal link. - If there is no
relvalue at all, the site is not qualifying its comment links. Google's guide allows this for trusted users: "If you want 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 over time." On a site with no moderation, read the other comments before adding your name next to them.
To check a batch of pages where you have already commented, SerpCrest's Bulk DoFollow / NoFollow Checker checks a list of URLs for live, dofollow and indexed status.
When a comment is worth writing
Treat a comment as a reply to a person, not a link placement. A rule of thumb we use: leave the comment only if you would still post it with the link field left blank. If you would, the comment can earn its place in one of these ways:
- It adds to the post. A data point, a counter-example or a fix for an error the author missed. If you pitch that author later, you can point back to it.
- It answers a reader. On an active post, other readers ask questions in the comments. A clear answer can bring clicks from people already interested in the topic.
Under the same rule of thumb, check four things before you pick a blog to comment on:
- The comments are alive. There are approved comments from the last few weeks, and the author replies to some of them.
- The readers are your readers. Read the questions in the comments and check that you could answer them well.
- The comments are moderated. Spam and signature links left standing mean nobody is moderating.
- The author matters to you. Pick people whose site you would like a mention or a link from later.
Skip it if the post is years old with no recent replies, the topic is unrelated to yours, or the comment section is already full of signature links.
How nofollow links relate to AI search is a separate question, covered in our post on nofollow links and AI search. For links an editor chooses to give you, start with what gets a guest post pitch accepted.
