Comment Backlinks
Comment backlinks are links placed in blog or article comment sections. Most are tagged nofollow or ugc and pass little value, and mass commenting for links is treated as spam.
Treatment of Comment Links
A comment backlink usually appears in one of two places. Most blog platforms let commenters add a website URL, which turns their name into a link. Some also allow links inside the comment text. Either way, the link sits in user-generated content that the site owner did not write.
Search engines treat these links with caution for that reason. A link in an article reflects the publisher’s choice. A link in a comment reflects only the commenter’s choice, and anyone can leave a comment. Google has no reason to see it as an endorsement from the website itself.
Most comment links also sit in a weak position on the page. Comment sections appear below the main content, often load after the article and get far less attention from readers. They rarely have topical context beyond the comment itself, and popular posts can carry hundreds of comments, each with its own link. Some sites also load comments through third-party systems, which makes comment links even harder for search engines to treat as part of the page.
As a result, comment backlinks pass little or no ranking value in most cases. They still count as backlinks in SEO tools, which is why some sites show thousands of “links” that do nothing for their rankings. In a backlink audit, a profile heavy with blog comments is usually a sign of old or low-effort link building rather than real authority.
Nofollow and UGC Attributes
Comment spam is the reason the nofollow attribute exists. In January 2005, Google introduced rel=”nofollow” with support from Yahoo and Microsoft, mainly to stop comment links from passing PageRank. Blog platforms adopted it quickly, and comment links have been nofollow by default on most sites ever since. It is one of the main reasons why some backlinks carry nofollow without the site owner ever choosing it.
In September 2019, Google added a more specific option: rel=”ugc,” which stands for user-generated content. It tells search engines that a link was added by a user rather than the publisher, which describes comment links exactly. WordPress, which powers a large share of blogs, now adds both nofollow and ugc to comment links by default.
Since March 2020, Google treats nofollow, ugc and sponsored as hints rather than strict rules. In theory, Google could choose to count a comment link. In practice, comment links remain one of the weakest link types, and nobody should expect them to lift rankings.
Some sites remove these attributes for trusted commenters as a reward for quality participation. Google has suggested this is acceptable. Even then, the link is still in a comment section, with all the limits that brings. For link builders, the practical result is clear: assume any comment link passes no ranking value, and judge commenting only by the traffic and relationships it brings.
Risks of Mass Commenting
In the 2000s, mass commenting was a mainstream SEO tactic. Software tools posted thousands of generic comments, such as “Great post, thanks for sharing,” with keyword-rich names like “Cheap Insurance Quotes” linking to commercial pages. Some of those tools still exist, sold alongside other black hat SEO tools.
Today, the tactic carries real downsides. Spam comments are caught by filters such as Akismet or deleted by moderators, so most never go live. The ones that do are usually nofollow and pass nothing. Google’s spam policies cover user-generated spam, and large volumes of comment links can form part of an unnatural link pattern.
There is also a reputation cost. Site owners recognize spam commenters quickly, and the brand name attached to spam becomes associated with spam. Many site owners block the domain entirely. Paid services that promise hundreds of “high DR” comment backlinks fall into the same trap. The links are usually nofollow, spread across unrelated blogs and easy for both moderators and algorithms to recognize.
During backlink audits, clusters of comment links with keyword anchors from unrelated blogs, often in languages different from your own, are a common sign of spammy links built by a past vendor or by someone running negative SEO. Google ignores most of them automatically, but they offer no benefit and should still be recorded in the audit.
Legitimate Comment Activity
Commenting still has a place when the goal is participation rather than links.
A thoughtful comment on a popular article in your niche can bring targeted referral traffic. Readers who scroll to the comments are engaged, and a useful insight often prompts them to click through. Adding a correction, a relevant data point or a practical example gives other readers a reason to notice you.
Comments are also a way to build relationships with writers and editors. Authors read comments on their own posts. Regular, intelligent contributions get noticed and can lead to guest post invitations, interviews or editorial mentions, which make far stronger links than the comment itself.
Active communities work the same way. Many niches have blogs and link building communities where regular contributors become known names. Forum links and other UGC links grow naturally from that kind of activity, alongside comment links.
A few rules keep comment activity clean. Consistency matters more than volume. A few useful comments a month on the blogs your audience reads will do more for your reputation than dozens of rushed replies.
Comment only where you have something real to add. Use your real name, not a keyword. Avoid links in the comment body unless they directly answer a question. Never comment at scale with templates. Treat any link as a small bonus rather than the reason for commenting.
Comment backlinks belong to an earlier era of SEO. Today, they pass little value and invite spam problems when built at scale. Comment where you can add something useful, and focus link building effort on placements that sit in real content.