Key Takeaway

Domain Authority (DA) is a score created by Moz, not Google, and is not used by search engines as a ranking signal. It is a third-party estimate of how well a domain might rank, based on its backlink profile. DA is useful as a rough comparative benchmark but should not be treated as a target metric or a reliable predictor of individual page rankings. Google's own signals — PageRank, topical authority, and content quality — are what actually determine rankings.

Last updated: June 2026

How to Check Domain Authority (And Whether It Actually Matters)

Domain Authority is one of the most cited metrics in SEO conversations and one of the most misunderstood. Site owners track it, agencies report it, and link builders use it to justify outreach decisions — yet it is a score invented by a third-party tool company, not a metric that Google uses or has ever used to rank pages. Understanding what DA actually measures, where it is useful, and where it misleads you is more valuable than knowing your current score.

This guide covers what Domain Authority is, how to check it, what it is genuinely useful for, and what metrics give you a more accurate picture of your site's actual authority in Google's eyes.

What Domain Authority actually is

Domain Authority is a proprietary metric developed by Moz, an SEO software company. It scores domains on a scale of 1 to 100, with higher scores indicating a stronger backlink profile. The score is calculated using Moz's own link index — the set of links they have discovered through their web crawl — and their algorithm for weighting those links by quality and relevance.

The key word is proprietary. DA is Moz's estimate of link strength, based on Moz's crawl data, using Moz's methodology. It is not a Google metric. It is not calculated from Google's data. Google has explicitly stated that it does not use Domain Authority or any similar third-party score in its ranking algorithm. When your DA goes up or down, nothing has changed in Google's systems — only in Moz's model.

Other SEO tool companies have their own versions of the same concept: Ahrefs calls theirs Domain Rating (DR), Semrush uses Authority Score, Majestic uses Trust Flow and Citation Flow. All of these are proprietary estimates based on each company's own link index and methodology. They often produce different scores for the same domain because they are drawing from different data and applying different algorithms.

How to check your Domain Authority

The most direct way to check Moz's DA score is through Moz's free tools. The MozBar browser extension shows DA for any domain you visit, and Moz's Link Explorer allows you to look up a domain's DA, see its top linking domains, and review its backlink profile in limited depth without a paid subscription.

Ahrefs' free tools include a domain authority checker that returns their DR score alongside basic backlink data. Semrush offers a limited free tier that shows Authority Score. All three are straightforward to use — enter a domain, get a score.

For checking your own domain's backlink profile with more depth than free tiers allow — and for comparing your link profile against competitors without a monthly subscription — Tom's Link Authority queries Common Crawl's 4.4 billion link graph directly from your desktop. It shows you which domains link to yours, how that compares to competitor domains, and where the link gaps are. The data comes from the same public web crawl that informs the major index-based tools, without the recurring cost.

Where DA is genuinely useful

Despite its limitations, DA has legitimate uses as a rough comparative benchmark. When you are evaluating whether a backlink opportunity is worth pursuing, a site with a DA of 60 is almost certainly a more authoritative link source than one with a DA of 10 — not because the score itself matters, but because it is a proxy for the underlying backlink profile strength, which does matter.

Similarly, when you are assessing the competitive landscape for a keyword, looking at the DA of the pages currently ranking gives you a rough sense of the authority bar you need to clear. If every top-ranking page is on domains with DA above 70, you are facing a competitive field where your site's link profile will need to be substantial to compete. If several top results are on DA 20 to 30 sites, the barrier is lower.

DA is also useful for tracking your own domain's trajectory over time — not as an absolute measure of your ranking potential, but as an indicator of whether your link building efforts are moving the needle on your backlink profile. A consistently rising DA over six to twelve months reflects a strengthening link profile, which is a positive signal even if the DA number itself means nothing to Google directly.

The mistake is treating DA as a target metric — optimising to increase your DA score rather than optimising to improve your actual rankings and traffic. These are related but not identical goals, and they diverge in ways that matter. A domain can have a high DA and rank poorly for its target keywords because its content is thin, its topical authority is diluted across too many unrelated topics, or its page-level signals are weak. A domain can have a modest DA and rank well because it has strong, focused content in a specific niche with just enough relevant backlinks to support it.

What Google actually uses instead

Google does not publish its ranking algorithm in detail, but through its documentation, patents, and the observable behaviour of its search results, we know something about what it values. The signals that most closely correspond to what DA is trying to approximate are PageRank and what practitioners call topical authority.

PageRank — the original algorithm that made Google's early search results so much better than the competition — measures the relative importance of pages based on the links pointing to them, weighted by the importance of the linking pages. It is a recursive measure: a link from a highly important page passes more value than a link from a low-importance page. Google still uses a version of PageRank internally, though it has been heavily developed and supplemented over the years.

Topical authority refers to how strongly a site is associated with a specific subject area. A site that has published extensive, high-quality content on a particular topic over time, and has earned links from other sites in that topic area, develops authority that is relevant to that topic specifically. A site with a high DA from links across dozens of unrelated topics may have lower topical authority for any one subject than a smaller, more focused site.

This distinction matters practically. If you are building a site in a specific niche, earning ten highly relevant links from respected sites in that niche is likely to do more for your rankings in that niche than earning fifty links from high-DA sites with no topical connection to your content. DA does not capture this distinction — it aggregates link strength without regard to topical relevance.

More useful metrics to track instead

If DA is a proxy metric of limited reliability, what should you track instead? Several metrics give you a more direct read on how your site is actually performing in search.

Organic traffic from Google Search Console is the most direct measure of search performance. If your rankings are improving, traffic goes up. If they are declining, traffic falls. No third-party score captures this as directly as the actual data from Google.

Average position in GSC for your target queries tells you where you are ranking for the keywords that matter to your business. Tracking this over time gives you a clear picture of whether your SEO work is moving the needle on the queries you care about.

Number of ranking keywords — the total count of queries for which your site appears in the top 100 results — is a useful breadth measure. A growing keyword footprint indicates that Google is indexing and ranking more of your content over time, which is a positive authority signal.

Referring domains — the count of unique domains that link to your site — is a more meaningful link metric than DA because it measures something concrete. Growing referring domain count over time, particularly from relevant sites in your niche, reflects genuine link profile development.

Using DA in link building decisions

The most practical use of DA in day-to-day SEO work is as a quick filter in link building. When you are reviewing a list of potential link prospects, DA gives you a rough first-pass quality signal. Sites below a certain DA threshold — say, DA 10 or 15 — are often very low quality directories, content farms, or newly created sites with no real audience. Filtering these out saves time in prospect qualification.

Above that baseline, do not rely on DA alone. A DA 30 site that is directly relevant to your niche, has a genuine audience, and publishes real editorial content is a better link source than a DA 50 site in a completely unrelated industry that happens to have a large link profile from its own past link building. Relevance and editorial quality are what make a link valuable, and DA does not measure either of those things.

The manual check described in the competitor backlink research process — visiting the actual page, assessing the content quality, checking for a real audience — gives you more useful information about a link prospect than its DA score in most cases. Use DA as a starting filter, not a final arbiter.

The honest take on DA as a goal

Plenty of agencies and consultants report DA as a key performance indicator for their SEO work. It is easy to understand, easy to present in a slide, and moves in response to link building activity — which makes it a convenient metric to show clients. That does not make it the right metric to optimise for.

If your DA is rising because you are earning good links from relevant sites and your content is improving, that is a positive development — but the thing actually driving your rankings is the links and the content, not the DA score that reflects them. If your DA is rising because you bought links from high-DA domains that have nothing to do with your topic, the score will go up while your rankings stay flat or decline.

Track DA if you find it useful as a rough comparative benchmark. Do not treat it as a goal. The goal is ranking well for the queries your audience is using, which is measured by traffic, position, and conversions — not by a third-party score that Google does not look at.

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