Domain Authority
Domain authority is a third-party score, not a Google metric, that estimates how well a site will rank in search based on the quality of its backlinks.
Domain authority is a predictive score created by Moz that estimates how likely a website is to rank well in search results based on the strength and quality of its backlink profile, running from 1 to 100.
What Domain Authority Means in Marketing
Domain authority is a number you will encounter constantly in SEO work, but it is important to understand what it actually is before you rely on it. It is not a Google metric. Google does not use Domain Authority in its ranking systems and does not publish an equivalent figure. DA is Moz’s own proprietary estimate, calculated from Moz’s web crawl data, intended to approximate how strong a domain is likely to rank.
That does not make it useless. Domain Authority is a practical shorthand for quickly assessing link quality when doing link prospecting, competitor analysis or reporting. If a site has a DA of 75, it almost certainly has a strong backlink profile and significant organic visibility. If a site has a DA of 5, it has almost none. The score correlates well enough with actual search performance to be a useful proxy.
The problem comes from treating it as a fact rather than an estimate. DA can fluctuate as Moz recrawls the web and updates its model. Your DA can drop even when your actual search performance improves. It can be gamed by acquiring large numbers of low-quality links. Understanding its limitations matters as much as knowing how to read it.
How Domain Authority Works
Moz calculates Domain Authority by analysing the backlink profile of a domain. The core inputs are the number of linking root domains pointing to the site and the authority of those linking domains, in a system where authority flows from link to link. A high-authority site linking to you transfers more authority than a low-authority site. Moz’s index of the web is large but not as comprehensive as Google’s, so DA reflects Moz’s crawl, not Google’s complete picture.
The logarithmic scale means that early gains are easy and later gains are hard. Going from DA 10 to DA 30 might require a modest link-building effort. Going from DA 60 to DA 70 requires sustained earning of high-quality links from major domains.
Competing tools produce similar scores under different names: Domain Rating (DR) from Ahrefs, Authority Score from Semrush, URLRating at the page level. These scores are not interchangeable: the same site can have materially different scores across tools because each uses its own crawl data and model.
Domain Authority Example
A regional news website might have a DA of 45: real editorial content, genuine links from other publications and a history of being referenced in its region, but not the scale of a national masthead. An e-commerce site selling niche products might have a DA of 20 despite doing excellent content marketing, simply because very few external sites have linked to it yet. Neither score tells you whether those sites rank well for their specific target queries; it only tells you something about their overall link authority.
Why Domain Authority Matters for Marketers
Domain Authority is a useful common language for quickly evaluating link prospects and benchmarking competitive positions in SEO. When you are deciding whether a potential link partner is worth pursuing, whether your site has comparable authority to competitors, or whether a site is likely to have genuine organic traffic, DA gives you a fast starting point. Use it as an input, not a verdict.
Frequently Asked Questions
Who created Domain Authority and what does the score mean?
Domain Authority (DA) is a proprietary metric created by Moz. It runs on a logarithmic scale from 1 to 100. Low scores are easy to achieve; scores above 50 represent genuinely strong sites; scores above 70 or 80 represent major publications, national brands and established institutions. Because it is logarithmic, moving from 20 to 30 is easier than moving from 60 to 70. The score is recalculated periodically and can fluctuate when Moz updates its index or its model.
Is Domain Authority the same as Google PageRank?
No. PageRank was Google's original link-based ranking signal, now evolved into a broader system of trust and authority signals Google does not expose publicly. Domain Authority is Moz's third-party approximation of how strong a domain is likely to rank, based on Moz's own web crawl data. Domain Rating (DR) from Ahrefs and Authority Score from Semrush are similar proprietary scores from competing tools. None of them are Google metrics, and none of them directly control your rankings.
Should you use Domain Authority to assess link opportunities?
As one signal, yes. A high DA site linking to yours is likely to pass more authority than a low DA site, all else being equal. But DA should not be the only filter. Topical relevance matters: a link from a DA 40 site that covers your specific industry may be more valuable than a DA 60 site with no topical connection. Real editorial context matters: a DA 30 niche publication that genuinely covers your space outweighs a DA 50 link farm. Use DA as a quick quality indicator, not as the final word.
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