SEMRush vs Moz Link Index Re-verified, Data Provided

I often do not post data along side these mini research projects such as my most recent brief comparison of SEMRush’s link index and Moz’s for a number of reasons. The primary reason is that publishing data often comes with risk such as data rights (publishing raw data from competitors is equivalent to giving that data out for free to users). However, if I am doing a comparison piece and the one of the compared providers requests the publication of the data, that is no longer a concern. Well, it seems that Oleg Shchegolev, CEO and Founder of SEMRush, was not confident in the results of the study and asked that I publish the data. I was out of town over the weekend, but I will happily oblige. I will make one quick retraction. I can’t say with...

SEMRush and Moz Link Indexes Compared

Historically, Moz has internally tracked comparisons with both Ahrefs and Majestic on a daily basis to ensure our Link Explorer product is a market leader. However, I have received several requests recently to compare Moz to SEMRush given their strides in growing a link index of their own. Below are the results of a simple study comparing index size based on the following metrics: Overall reported backlinks (Self Reported) Likelihood Moz or SEMRush reports more referring domains to a domain (Sample Size: 1000 domains) Likelihood Moz or SEMRush reports more backlinks to a domain (Sample Size: 1000 domains) Likelihood Moz or SEMRush reports more referring domains to a URL (Sample Size: 1000 URLs) Likelihood Moz or SEMRush reports more backlinks to a URL (Sample...

Update to Moz Link Index Comparison Metrics

Here is an update to my post on Moz called “Big, Fast, Strong“. I give the definitions for all these metrics in that post, so I wont repost them here. I started with the only one we aren’t in first place or tied for first place, which is the fastest crawler. That honor still goes to Ahrefs. The rest of the metrics, well, they speak for themselves.   Ahrefs Still has the fastest crawler. Moz and Majestic are neck-and-neck on domain index matches, while Ahrefs is a few % behind. Moz is winning Google URL Index Matches Moz is winning Domain Root Linking Domains Moz is winning URL RLDs Moz is winning backlink counts for domains Moz is winning backlinks to URLs   Moz is in a dead heat with majestic for domain being present in index  ...

In Defense of Domain Authority

With the launch pending for Moz’s much improved Domain Authority metric, the debate has once again been resurrected on whether Google uses Domain Authority and whether it is worthwhile. Let me take a few minutes of your time to unpack this question fully. First, Google has quite unambiguously stated that they do not use Domain Authority in their search algorithms. I take their word on this. Not only do I know Google does not use Moz’s Domain Authority, I do not believe they have a pre-calculated metric that approximates a domain or site authority in general. But what follows from these statements? Does this mean that domain level metrics have no impact on rankings? Does this mean that DA has no value to search engine optimizers? Let’s address...

Measuring Link Index Freshness

Disclosure: I work for Moz. One of the hardest metrics to compare link indexes on is their percentage of “live links”. At first, it seems like a simple endeavor – just download the backlinks and check if they are live. It turns out that the process is far more complicated for a number of reasons. Redirect chains may not include the target domain in the URL, and there is no way to know which outlink begins the redirect chain without following every outlink on that linking page. Links aren’t always links – does the index count form action as a link? iframe? embed src? Linking sites might be temporarily down (do you count that as a missing link or ignore it). How do you know if it is temporary or permanent? Different indexes have...

Keyword Volume Relational Accuracy

First, quick disclosure: I am Russ Jones, Principal Search Scientist at Moz and I work directly on the model that predicts search volume. It is impossible to know the exact search volume for a keyword in Google. The methodologies available to us (Google Adwords Keyword Planner, Traffic Estimator, and Google Trends) are all problematic in one way or another. But this doesn’t mean we are hopelessly lost regarding our predictions of search volume. One thing we can analyze is the relationship between keywords rather than their exact volume. For example, Google Trends doesn’t provide us the exact search numbers, but it does provide us a comparison of keywords. Theoretically, the relationship between 2 keywords in Google Trends (lets say 3:1 because keyword...