SEMRush is on Your List of Prospective SEO Tools, but is It Accurate?

In this post, I’m going to run a few of my client sites through SEMRush and compare it to the data in their Google Analytics accounts.  I won’t be sharing any client names, but you’ll see that there are some striking conclusions that this comparison can help you to come to.

Comparison #1

This is a law firm that we have been working with for some time.  The site recently suffered a negative SEO attack, so the numbers in the analytics account are unreliable between August and October 2017, so we’re going to omit any analytics data from before that date.

SEMRush Data Site #1

data from SEMRush about a law firm website

Google Analytics Organic Traffic

google analytics chart to compare with semrush

SEMRush’s Estimate of Organic Traffic

While the tool is definitely in the ballpark—the site is drawing in the hundreds, not the thousands or millions of monthly visitors—it underestimated the site’s actual organic traffic by 75%.  SEMRush estimates 108 visitors in January 2018, but analytics show that the number was actually 488.  Additionally, the increase in traffic that it estimates for March was reflected in the analytics, but it was not as pronounced as the tool would lead you to believe.

semrush comparison with paid search analytics
SEMRush’s Estimate of Paid Traffic

The tool’s paid search traffic estimate is unusable.  It didn’t even pick up the traffic until September of 2017 and even when it did, it vastly under reported the amount of traffic.

semrush comparison of backlinks with ahrefs

SEMRush’s Estimate of Backlinks

Since Search Console is rather unreliable when it comes to reporting backlinks, we used Ahrefs.  Apparently, SEMRush has found 200k+ more backlinks to this site than Ahrefs has.  As I wrote earlier, this site did suffer a negative SEO attack (which didn’t really have any sort of noticeable effect on rank) but the tool seems to have done a better job of finding these spam links than Ahrefs did.

Comparison #2

This is a high traffic entertainment business that is highly seasonal.  Its peak season is in the Summer and Fall and it actually closes in Mid-Winter.

semrush metrics for site 2

analytics of site traffic to compare to
SEMRush’s Estimate of Organic Traffic

As you can see, this business has volatile organic traffic, but SEMRush did not pick up on it at all.  The site saw ballpark numbers of 9k visitors per month, then 35k in October, but the tool tracked it as getting a steady 20k or so.

This client does not do any PPC and SEM Rush correctly picked up on it.

SEMRush’s Estimate of Backlinks

ahrefs backlinks found

In this case, SEMRush did not find as many backlinks as Ahrefs, but it was comparably in the same ballpark as Ahrefs.

The Verdict: SEMRush is Getting Better at Finding Links but Struggles to Estimate Traffic

It found a lot of spam links

I was surprised to see that SEMrush found so many more backlinks for site #1 than Ahrefs.  Site #1 did suffer a negative SEO attack and SEMrush did a better job of finding many of those links; this is just one case, but maybe it is a valuable tool for creating disavow files following negative SEO attacks…

Estimating organic traffic is all guesswork.

You have to know what keywords a site ranks for, the estimated number of searches for that term, and the likely CTR based on its position.  Ahrefs and Similarweb aren’t particularly reliable for this data either.  The conclusion that you should come to is that these tools are useful if you want to tell if a site is getting traffic in the hundreds, thousands, or millions, but don’t use them to compare your analytics data with that of another site.