If you’ve been working with SEOs for a while, you’ve probably heard a lot about domain rating. And you’ve probably found teams that considered domain rating a KPI. You’ve probably landed on this post because you’re asking yourself a very simple question: Is domain rating important?
And, is it a metric you should have in mind for your 2023 SEO efforts?
In this post, we’ll compare Ahrefs, SEMrush, and Moz domain rating metrics and try to answer these questions.
We will cover:
- The concept of Domain Rating and its purpose
- How Ahrefs, Semrush, and Moz evaluate domain rating
- How Google actually crawls sites
- Our conclusions
Let’s dive in!
What Is Domain Rating and What Is It for?
First things first: What is domain rating?
DR (Domain Rating) is a metric determined by the quality and quantity of backlinks acquired by a domain. Theoretically, domain rating reveals a website’s authority. And, according to DR enthusiasts, search engines can detect it and rank websites based on domain rating.
When a high quality domain links to another domain’s content through a dofollow link, it indicates an endorsement of that content’s quality. According to the theory behind DR, this would signal to search engines that the content is authoritative, original, and relevant to the subject.
Need ideas to get quality links? Check out our link-building guide
As we mentioned, numerous companies such as Ahrefs, Moz and SEMRush have incorporated tools that quantify your overall domain score based on backlinks. Having a clear picture of how their scoring systems differ is key to understanding what DR is truly about.
Let’s dive into it.
Domain Authority, Domain Rating & Authority Score: the Same Thing under Different Names?
Each major SEO tool has its own system to measure domain authority.
- Domain Authority (Moz)
- Authority Score (SEMrush)
- Domain Rating (Ahrefs)
Each system is based on the information each tool gathers about domains.
Let’s dive into each company’s DR assessment tools before moving on to how Google really works.
Ahrefs: Domain Rating as a Prominent Metric
Most of Ahrefs’ tools and reports include domain rating metrics. But is it really that important?
Technically, Ahrefs calculates domain rankings by:
- Searching for all domains with at least one dofollow link to the target domain.
- Quantifying the number of domains each domain links to.
Then, if the domain ranking is high (on a scale of 1 to 100), this means that “link juice” is transferred to the linked domains. Link juice is calculated by dividing the DR of the linking domain by the number of unique domains it links to.
Keep in mind that the Ahrefs DR metric is based exclusively on links. According to the company, search traffic, domain age, or popularity of a parent brand are not considered.
One thing worth mentioning is that Ahrefs DR does not differentiate between quality links and spam links. In fact, low (or very low) quality backlinks can increase your DR instead of decreasing it.
Moz: Machine Learning for DA Rankings
According to Moz, domain DA is calculated using a machine learning algorithm that predicts how frequently Google favors a domain. They make it clear that their model is built based on “what we know about the links pointing to it.”
So basically, the domains that rank the highest will have a higher DA.
Semrush: Authority Score
Semrush bases its Authority Score on a machine learning algorithm that measures quality, popularity and backlink signals.
First, the algorithm considers organic search data, website traffic data and backlink data to understand the ranking of popular domains. Then, a second algorithm uses backlink data to detect if the domain is perceived as authoritative.
Metrics used in this calculation include:
- Referring domains pointing to the site and their authority
- Follow vs. nofollow links pointing to the site (inbound links)
- Follow vs. nofollow links pointing away from the site (outbound links)
- Outbound links from each referrer domain
- The specific backlinks pointing to the site
- The referrer IPs pointing to the site
- The referrer subnets pointing to the site
Authority Score is measured on a scale from 0 to 100.
How Does Google Actually Crawl Sites?
Prior to answering this question, you should keep in mind that all three companies offer their clients the same warning about domain rankings.
Semrush warns that:
“You should not rely on one of them (the factors that determine DA) individually (…). Gaining a higher Authority Score is always about the cumulative effect of all your SEO efforts.”
Ahrefs states that:
“…you should not focus your efforts on growing this metric specifically. Google ranks pages, not websites. So your efforts should, therefore, be focused on producing high-quality content and acquiring high-quality backlinks directly to that content.”
Or as Moz puts it:
“This score can then be used when comparing websites or tracking the ‘ranking strength’ of a website over time. Domain Authority is not a Google ranking factor and has no effect on the SERPs.”
What we know for sure is that Google only covers a part of the whole internet. For a wide variety of reasons, Googlebot doesn’t have access to all the online content in existence. And, aside from the best practices that Google advocates for and some reverse engineering, we don’t really know how the search engine operates.
From the totality of the content that bots can crawl, Google only indexes a relatively small selection. And then, it tries to assess what’s the most valuable answer to each query. So far, we know that Google’s guided by user behavior metrics, backlinks, how often content’s updated, and even social signals, among other factors. But those assumptions are not enough to develop a reliable score around Google’s preferences.
Cutting to the chase: We don’t really know how big the internet is. And we don’t know exactly how much of it is crawled and indexed by Google. And we know even less about which specific links Google considers when assessing content quality.
So, is domain rating really important for SEO? In short, the real problem with metrics calculated in third-party link indexes is that they are not directly related to the Google ecosystem. We don’t know the magnitude of the deviation with respect to Google and we don’t even know if this deviation is constant for each domain.
Thus, domain ratings present some conceptual problems:
- Link index size: The size of the SEO software’s link index is not as comprehensive as Google’s.
- Different coverage: Since we don’t know which URLs Google crawls, it is most likely that the providers’ crawlers don’t fully match Google’s.
- Different ranking: We don’t know which links Google evaluates, and the difference between each provider’s score for the same domain signals that they don’t do either.
- No comparability: third-party link indexes cannot be trusted to map different domains with a constant level of errors. The degree of deviation from Google varies depending on the domain environment.
To conclude, it must be said that Google does not use any of these tools as a factor in its algorithm. Domain rating is only a predictive tool to evaluate a domain’s potential for ranking.
Back in the day (we’re talking late 1990s/early 2000s), Google used a metric similar to DR/DA/Authority Score. It was called PageRank, and it measured how authoritative a website was on a scale from 0 to 10. Ever since its early days, Google has aimed to rank content by assessing its value.
PageRank hasn’t been available to SEOs for over 10 years. But as Google’s John Mueller said on Twitter in 2020, Google is still using it.
Yes, we do use PageRank internally, among many, many other signals. It's not quite the same as the original paper, there are lots of quirks (eg, disavowed links, ignored links, etc.), and, again, we use a lot of other signals that can be much stronger.
— 🌽〈link href=//johnmu.com rel=canonical 〉🌽 (@JohnMu) February 24, 2020
However, PageRank’s algorithm isn’t the same as it was in 1997, and it doesn’t have anything to do with DA, DR, or Authority Score.
PageRank is one among many other ranking factors that Google keeps secret. That secrecy keeps SEOs focused on creating valuable content instead of trying to hack the algorithm.
That said, domain ranking and domain authority metrics are not completely worthless. Far from it! You can use these metrics as a general guide when building backlinks and tracking SEO progress. But domain rating shouldn’t be your north star.
Make Technical SEO Your Competitive Advantage
Yes, domain rating is a somewhat useful tool. However, you shouldn’t neglect comprehensive SEO. Changes in your sitemaps? New canonical tags? Changes in your keywords or meta descriptions? SEORadar is a monitoring tool that watches your code 24/7 and instantly notifies you of any SEO-related changes.
With SEORadar, you can take action quickly and preserve your rankings. In addition, all notifications can be customized according to your priorities and preferences.
Technical SEO doesn’t have to be exhausting. Even at scale, SEORadar has you covered.