What Is Domain Authority and Does It Actually Matter

Where Domain Authority Comes From

Moz created the Domain Authority metric in 2010 as a way to estimate how well a website would rank based on factors Moz could measure externally, primarily the number and quality of backlinks pointing to the domain. The score is calculated using Moz's own link index and machine learning model, and it is updated regularly. A brand new domain starts at a DA of 1, while the largest sites in the world like Wikipedia and Google.com score in the upper 90s.

Other SEO tools created similar metrics: Ahrefs has Domain Rating (DR), Semrush has Authority Score, and Majestic has Trust Flow. Each tool calculates its score differently using its own data, which is why the same website can have a DA of 35 in Moz, a DR of 52 in Ahrefs, and an Authority Score of 41 in Semrush. None of these scores are used by Google.

Why Google Does Not Use Domain Authority

Google has explicitly denied using any third-party authority metric. Google's John Mueller has stated that Domain Authority is not something Google looks at and that websites should not obsess over it. Google has its own internal systems for evaluating site quality and trustworthiness, and those systems are far more sophisticated than any third-party estimate.

Google evaluates authority at the page level, not just the domain level. A high-authority domain can have individual pages that rank poorly because those specific pages lack relevance, depth, or backlinks. Conversely, a relatively unknown domain can rank well for specific queries if individual pages are exceptionally relevant and well-linked for those topics. This is why focusing solely on domain-level metrics misses the full picture of how Google evaluates rankings.

When Domain Authority Is Actually Useful

Despite not being a ranking factor, DA is a helpful tool for several practical SEO tasks.

Competitive analysis. Comparing your DA against competitors gives you a rough sense of the competitive landscape. If the top-ranking sites for your target keywords all have DA scores above 70 and yours is 15, you know you are facing a significant authority gap that will take time and effort to close. This helps set realistic expectations and guides keyword targeting toward terms where the competition is more achievable.

Link prospecting. When evaluating potential backlink sources, DA helps you quickly filter sites. A link from a DA 60 site is generally more valuable than a link from a DA 10 site, because higher-DA sites tend to have stronger backlink profiles themselves, which means they pass more authority through their outgoing links.

Tracking progress over time. Watching your DA increase over months and years is a rough indicator that your overall link profile is growing. It is not precise, and short-term fluctuations are meaningless, but a DA that climbed from 15 to 35 over a year suggests your site is gaining genuine authority.

Why You Should Not Chase Domain Authority

The biggest mistake is treating DA as a goal rather than a side effect. Buying links to inflate your DA, participating in link exchanges, or publishing guest posts solely for the backlink are tactics that might increase your DA score without actually improving your Google rankings. Google's spam detection systems are sophisticated enough to identify and discount manipulative link building.

A high DA does not guarantee rankings, and a low DA does not prevent them. Plenty of sites with modest DA scores rank on page one for competitive keywords because their specific pages are the best match for those queries. Backlinks still matter, but the value comes from the links themselves and the authority they pass, not from the third-party score that tries to summarize them.

What Google Actually Uses Instead

Google's internal system for evaluating site and page authority is based on PageRank (which still exists internally, though the public toolbar version was discontinued in 2016), along with neural network models that evaluate content quality, E-E-A-T signals, and topical relevance. Google also uses signals like brand searches (how often people search for your brand name), mentions across the web, and the overall quality profile of your content.

Rather than trying to increase a third-party score, focus on the fundamentals that build genuine authority: publish expert content that earns natural backlinks, build topical authority through comprehensive coverage, ensure your site is technically sound, and be transparent about who you are and what qualifies you to write about your topics.