Google retired the PageRank browser tool in 2016. Since then, search engine optimizers have sought alternatives to site authority.
This is because links, especially those from trustworthy sites, are an important ranking factor. SEOs need metrics to know if a site is worth the effort of link solicitation.
Therefore, there is a mishmash of industry calculations for assessing site trust and popularity.
Moz was one of the first platforms to have its own web index, and in 2019 it facilitated the replacement of two of its own PageRank toolbars: Page Authority and Domain Authority. Both are out of 100, with higher scores indicating higher reliability.
Even now, Moz doesn’t say much about how they calculate these metrics. We provided a vague description at launch. “It’s based on data from the Mozscape Web Index, which includes link counts, MozRank and MozTrust scores, and dozens of other factors.”
Another SEO platform, Majestic, also developed an early alternative to PageRank. It’s called the “quote flow”. It measures the “power” of a website or link on a scale of 100.
Ahrefs’ metric is called Domain Reputation. It measures the “strength of the target website’s overall backlink profile (in terms of size and quality).”
The Semrush ranks described below are based on organic rankings.
Domain Authority has nothing to do with Google. That alone makes it an unreliable indicator for optimizing organic search rankings. How Google determines a page’s authority can only be guessed.
Additionally, Google never used domain-level metrics in their ranking algorithms, only page-level metrics. According to Google, domain authority (the accumulation of all links pointing to that domain) does not guarantee high rankings.
There is no single way to measure page authority. However, you can cite signals that infer page authority.
- traffic source. Does your site receive clicks? From where? The best types of links are those that generate visitors. SimilarWeb and Alexa estimate site traffic and sources, as do other tools.
- Organic search rankings and traffic. A page (or site) that ranks highly and gets organic traffic may have a backlink profile that Google likes (among other factors). Semrush rank is worth it in my experience because it’s based on your site’s organic ranking. Ahrefs’ “Traffic Value” estimates the value of a domain’s organic traffic from pay-per-click advertising. Ahrefs also estimates the organic traffic for each page, which helps.
- manual review. Finally, a quick look at a page or site will almost always tell you if the page or site is trustworthy and therefore worth asking for backlinks. Is the author a real person? Can authors be found elsewhere, such as LinkedIn or other sites? Do you have a transparent and informative “About Us” page?
If you were using domain authority to evaluate potential backlinks (or disavows), stop now. Domain authority does not accurately represent a site’s credibility or ranking potential. There are better methods of evaluation, such as manual review.