Blog comments have long held a very prominent position in Search Engine Optimization (SEO) debates. For anyone familiar with the subject, it should be relatively easy to see why.

Back in 2005, Google introduced the “nofollow” tag as a partial response to comment spam. Today, Google’s PageRank draws attention to page authoritativeness, which comment backlinks affect. Finally, comment sections produce social signals for search engines that affect SEO. Nonetheless, it’s not a clear-cut subject, as debates will frequently show. Thus, let us explore just how comments on your blog can impact search rankings and potential courses of action.

Blog Comments: Misconceptions And Oversimplifications

First and foremost, it is crucial to establish a firm, data-backed understanding of this subject. It has been a subject of tremendous debate over the past decade, at the very least, for a plethora of reasons.

Perhaps the most significant one lies in Google themselves, as they have never fully disclosed their algorithms. Thus, many professionals have had to substitute concrete knowledge with estimations, predictions and their own content marketing research for years. In turn, many conclusions can be questionable, flimsy or warrant scrutiny – yet many such conclusions circulate the internet today.

Thus, to delve into how comments on your blog can impact search rankings, let’s begin by addressing three widespread misconceptions.

#1 “Comments On Your Blog Don’t Affect Search Rankings”

This one is likely the most frequent claim against blog comments. Many proponents of this claim support it through research like this study by Hubspot on the subject.

Now, labeling this claim as an inaccuracy or oversimplification absolutely doesn’t mean to discredit Hubspot themselves. After all, they haven’t actually claimed blog comments don’t affect search rankings either. Their three conclusions are, verbatim, the following:

• “There is no correlation between the number of comments on a post and the number of views that post got.”
• “There’s also no correlation between comments and the number of links that post got.”
• “There is some positive correlation between views and links.”

All three of these statements seem to be factually correct and supported by the study. However, none of these conclusions directly prove, or claim to prove, that blog comments don’t affect search rankings.

On the contrary, OptinMoster cites an interesting study by Neil Patel on the subject that does explore search rankings. Admittedly, Neil Patel had a much smaller sample size than Hubspot. They also seem to have used different methodologies and gauged results through other metrics. Nonetheless, Neil Patel did identify that “26.7% of the keywords that were ranking in Google were from the comments section.”

Furthermore, various Google employees have made similar statements over the years. For example, TheSemPost cites Google’s Gary Illyes responding to inquiries on search ranking as such:

“In general if we see that there’s a healthy, thriving community on a site, that can help a lot.”

As such, one can safely claim that comments on your blog do impact search rankings. In fairness, one may not know the exact extent of this impact, but it’s false to assume there is none.

#2 “Comments On Your Blog Don’t Generate Traffic”

Next, a frequent claim is that blog comments don’t generate traffic. This one is likely more of an oversimplification, but it’s still a dubious claim.

Some may cite Hubspot’s study mentioned above to prove this claim. Technically, in isolation, it seems to be true; comments by themselves don’t generate traffic. However, a counterpoint lies in Neil Patel’s aforementioned study as well. After identifying that keywords in comments were ranking, he found that 16% of all traffic came from comments.

Alongside this argument, we can return to Garry Illyes’s claim; communities help with SEO. The correlation here should thus be that blog comments create SEO-friendly factors, which in turn increase traffic:

• A thriving community
• Social signals through engagement
• Content length and value

Finally, case studies on the correlation of comments to blog traffic, like this one from ShoutMeloud, should solidify this conclusion.

Thus, this claim can indeed mislead. One can certainly debate the exact extent of the impact of comments on ranking or whether it’s worth the effort. But blog comments do generate traffic because they affect SEO.

#3 “Search Engines Treat Comments On Your Blog As a Part Of Your Post’s Content”

Finally, this claim for blog comments is also widespread. It is by no means completely false; it’s actually mostly true. However, from theory to practice, it too can mislead.

It seems that a very common misunderstanding stems from this claim; that search engines treat content and blog comments identically. It thus follows that one can simply add the comments’ word count to their contents’ word count. That is absolutely not the case, as the SearchEngineJournal cites Google’s John Mueller to explain:

“From our point of view, we do see comments as a part of the content. We do also, in many cases, recognize that this is actually the comment section so we need to treat it slightly differently.”

Along similar lines, in his aforementioned conversation, Gary Illyes also differentiated the two, saying:

“It feeds into general quality. Say, there’s good content, 5 points, great links from great pages, 2 points, thriving community, 1pt.”

Thus, we can safely conclude that the content’s actual word count and comments are not identical. Search engines indeed factor in the comments’ links, quality, and word count, as studies show. However, that’s not the same as simply adding the two word counts together as if they’re identical. Instead, it’s much safer to simply meet the desired word count within the content itself without presupposing comment length. Longer content ranks better, in either case, so comments will remain valuable in this sense regardless.

How Comments On Your Blog Can Impact Search Rankings

Having clarified these subjects, we may delve into exactly how comments on your blog can impact search rankings. The sources cited above, and others, will be crucial here, as we bridge theory and practice.

#1 Blog Comments Provide Latent Semantic Indexing (LSI) Keywords

Initially, one can identify LSI keywords as a factor in how exactly blog comments enhance content ranking. In his study above, Neil Patel found that a portion of ranking keywords came from comments. While he doesn’t explicitly identify them as LSI keywords, it should seem plausible that they are.

Many assume that, in essence, LSI keywords are synonyms or variations of keywords for which the blog post ranks. For example, a post on shoes may target keywords like “shoes”, “boots”, and “sneakers”, but there are many related keywords. Thus, comments that mention “trainers” or “high heels” would add to the keywords the post ranks for.

It is noteworthy, however, that this doesn’t seem to be the case. In fact, some argue that LSI keywords aren’t even “a thing”, like SearchEngineJournal. Others, like Backlinko, argue that they are, and that they impact rankings.

However, before arguing whether LSI keywords have an impact, the latter make a crucial point on what they are. They propose that they are “terms that are closely tied to your target keyword”, as opposed to synonyms. Thus, in the above example, “trainers” and “high heels” wouldn’t be LSIs for “shoes”; “running“, “exercise” and “training” would be.

Therefore, natural, non-spam comments would realistically add LSIs to one’s blog. However, one can do little but attract vast audiences that leave long, insightful comments that include LSIs. It is not a factor one can force or actively work toward. One can, however, curate comments and prioritize those that have LSIs. Still, this too comes with some caveats, as we’ll discuss below.

#2 Content Length

Next, increased content length factors into how comments on your blog can impact search rankings. The sources cited above should establish that comments do indeed increase content length, even though they’re not identical.

That content length affects SEO, and thus search rankings, is well documented. That’s where the “golden word counts” of 1,000, 1,500, and even 2,000 words stem from. While, as highlighted above, comments shouldn’t be presupposed to reach these word counts, they do add to content length. Even if they’re treated “slightly differently”, as John Mueller states.

Still, one can argue it’s not length alone that adds to SEO; rather, it’s the quality that frequently follows length. Insightful, informative content tends to be thorough, so the two overlap. What’s more, soliciting comments to add to content length also frequently hinges on content quality.

#3 Content Quality

On the subject of content quality, then, comments can also add to overall content quality. In the above discussion, Gary Illyes mentioned that quality “can help a lot”, even if it’s found in the comments.

To bridge the two benefits, length and quality, one must wonder how to solicit comments to begin with. If comments on your blog can impact search rankings, how can you solicit comments if you frequently get few to none?

The answer seems to reside in SEO’s own fundamental tenet; “quality is king”. If your content offers attractive length, high quality, and useful insights, it will attract commenters who value them. In turn, simply encouraging readers to “leave a comment” or “share their thoughts” should provide a solid foundation. Finally, using interactive content is always a viable strategy to incite engagement.

#4 User Engagement And Community

Similarly, soliciting comments overlaps with user engagement signals and what Gary Illyes dubbed a “thriving community”. Comments can provide such signals before social media strategies do.

As highlighted above, these signals do indeed impact search rankings. Consider the core principles of SEO in terms of user engagement, in social media or otherwise. Engagement signals include:

• Likes and shares
• Reactions and comments
• Referrals

Search engines use such signals to gauge engagement and, by extension, quality. Blog comments do offer such metrics themselves, albeit to a lesser extent, and can thus impact search rankings.

#5 Expertise, Authoritativeness And Trustworthiness (E-A-T)

Finally, all of these factors orbit around E-A-T in one form or another. Google’s PageRank hinges on this trio of attributes, so it’s a cornerstone of SEO. While comments arguably don’t have a massive impact on it, they do seem to have some effect.

Initially, Google helpfully explains that Search Quality Raters help its search algorithm. Furthermore, TheSemPost cites John Mueller saying comments do affect judgments of quality. Specifically, that they may wonder, “Is this overwhelmingly bad? Is this overwhelmingly good? Where do we draw the line?”

Indeed, comments help visitors vet the quality of a blog. They may provide further insights, relevant links to authoritative sources and corrections. In contrast, of course, negative comments and “flame wars” can have an adverse effect. That’s, in part, why some blogs welcome and encourage comments while others curate them or simply disable them.

To Allow Or Disable Blog Comments

Finally, having discussed how comments on your blog can impact search rankings, two reasonable questions may arise. For one, should one allow or disable blog comments? Second, assuming one allows them, should they be curated?

On the former question, Fizzle’s Corbett Barr held a debate between two prominent bloggers, Pat Flynn and Everett Bogue. Among other arguments, Pat argued for blog comments because they incite conversations, which inform creative decisions. Arguing against blog comments, Everett claimed that moderating comments took too much of his time and thus taxed his creativity.

While this debate can serve as a cursory glance into the topic, it’s arguably quite subjective. On the objective front, John Mueller warned that deleting comments outright would not come without adverse effects. As such, doing so should likely be seen as a calculated risk.

To Moderate, Curate, And Delete comments

Finally, on the latter question, moderation seems to be imperative. There are indeed many pros and cons to comments, many of which affect search rankings. But without moderation, any comment section can devolve into a liability.

Still, a final factor is worth highlighting here. Curating comments may help with quality, civility, LSIs, and more. However, it’s noteworthy that active commenters may not take kindly to deleted comments. Indeed, selectively removing comments like “great post” may not harm rankings directly, but it may dismay or anger well-meaning commenters. As such, this too should be seen as a calculated risk instead of an easy choice.

Conclusion

To summarize, comments on your blog can impact search rankings in many ways. Whether through increasing your content’s length and quality, adding LSIs, sending social signals or other means, they do. However, they’re not without risks, and they can have adverse effects if left unchecked. Thus, careful research and case-by-case choices can only be helpful.