Google discontinued its PageRank browser tool in 2016. Since then search engine optimizers have sought an alternative measure of a site’s authority.
That’s because links remain a key ranking factor, especially links from trustworthy sites. SEOs need a metric to know if a site is worth the link-solicitation effort.
Thus we now have a mishmash of industry calculations to assess a site’s trust and popularity.
Moz was among the first platforms with its own web index, which facilitated in 2019 two proprietary PageRank toolbar replacements: Page Authority and Domain Authority. Both are a 100-point scale — the higher the score, the more authoritative.
Even now, Moz doesn’t much explain how it calculates those metrics. It offered a vague explanation at launch: “It is based off data from the Mozscape web index and includes link counts, MozRank and MozTrust scores, and dozens of other factors.”
Majestic, another SEO platform, also developed an early-day PageRank replacement. It’s called “Citation Flow.” It measures the “power” the website or link carries on, also, a 100-point scale.
Ahrefs’ metric is called Domain Rating. It gauges “the strength of a target website’s total backlink profile (in terms of its size and quality).”
Semrush Rank, addressed below, is based on organic rankings.
Domain authority has nothing to do with Google. That alone makes it an unreliable metric for optimizing organic search rankings. Google’s equivalent is likely entirely different with its own formula, spam signals, page history, and more. We can only guess how Google determines a page’s authority.
Moreover, Google never used a domain-level metric in its ranking algorithm — only page-level metrics. Domain authority — the accumulation of all links pointing to that domain — never guarantees high rankings, per Google.
There is no single way to measure a page’s authority. However, we can cite signals that infer the authority of a page.
- Traffic sources. Does the site receive clicks? From where? The best type of link is one that generates visitors. SimilarWeb and Alexa estimate a site’s traffic and sources, as do other tools.
- Organic search rankings and traffic. A page (or a site) that ranks well and garners organic traffic likely has a backlink profile (among other factors) preferred by Google. Semrush Rank is worthwhile in my experience as, again, it’s based on a site’s organic rankings. Ahrefs’ “Traffic Value” estimates the worth of a domain’s organic traffic if it came from pay-per-click ads. Ahrefs also estimates the organic traffic of each page, which is helpful.
- Manual review. Finally, a quick look at a page or a site can almost always indicate whether it’s trustworthy and therefore worth pursuing for backlinks. Are the authors real humans? Can you find the authors elsewhere, such as on LinkedIn or other sites? Is there a transparent and informative “About Us” page?
Stop now if you’ve been using domain authority to evaluate potential backlinks (or disavows). Domain authority is not a reliable representation of a site’s trustworthiness or ranking potential. There are better ways to assess — such as a manual review.