Domain Authority is a score from 1 to 100 that predicts how well a website will rank in search results, based on the quality and quantity of links pointing to it
Domain Authority (DA) was created by Moz, a company that builds SEO tools. It is not a Google metric — Google does not publish a "domain authority" score. Instead, Moz built their own ranking system to help people understand which websites are likely to rank higher than others.
The score works like this: a website with a DA of 75 will generally outrank a website with a DA of 25 in search results, all else being equal. But "all else" is rarely equal. Domain Authority is one signal among many that Google actually uses, and it is not the most important one.
Key Takeaways
- Domain Authority is calculated by Moz using a machine learning model trained on Google's actual ranking data, not by Google itself.
- The score depends almost entirely on the number and quality of external links pointing to your site, weighted by the authority of the linking sites.
- A higher DA does not may provide higher rankings — it is a prediction tool, not a ranking factor that Google uses directly.
- Your DA can fluctuate month to month because Moz updates their model and the web changes constantly.
- You can check your domain's DA for free using Moz's toolbar or by entering your URL on their website.
What goes into the Domain Authority calculation
Moz does not publish the exact formula they use. What they have said publicly is that DA is built on a machine learning model — a system trained on millions of websites to learn which characteristics predict high Google rankings. The model looks at hundreds of factors, but the strongest signal is backlinks: links from other websites pointing to yours.
Not all backlinks are equal. A link from a website with a DA of 80 carries far more weight than a link from a website with a DA of 10. This creates a feedback loop: if you get a link from a high-authority site, your own authority rises. If you get links from low-authority sites, the boost is smaller.
The model also considers the relevance of the linking site to yours. A link from a technology blog to a software company matters more than a link from a random directory. Moz's system learns these patterns from data, not from a human-written rule.
Why Domain Authority changes month to month
Your DA is not fixed. It shifts because two things are always changing: the web itself, and Moz's model.
On the web side, you gain and lose links constantly. A site that linked to you might delete the page. A new site might link to you. Competitors gain links. The overall link landscape shifts, and your position within it shifts with it.
On Moz's side, they update their model regularly — sometimes monthly, sometimes less often. When they retrain the model on new data, every website's DA can move, even if nothing on your site changed. This is why you might see your DA drop even though you have not lost any links: Moz recalibrated how they measure authority.
How Domain Authority differs from what Google actually ranks on
This is the most important thing to understand: Google does not use a "Domain Authority" score. Moz created DA as a prediction of how Google ranks sites, not as a ranking factor itself.
Google's actual ranking system is far more complex. It weighs on-page factors like content quality, keyword relevance, and page speed. It looks at user behavior signals like click-through rate and time on page. It considers the freshness of content and the trustworthiness of the site. Links matter, but they are one piece of a much larger puzzle.
A site with a high DA can still rank poorly if its content is thin or irrelevant. A site with a lower DA can rank well if it has better content and better user signals. Domain Authority is useful as a rough benchmark — "this competitor's site is probably stronger than mine" — but it should not be your only metric.
How to check your domain's authority score
Moz offers a free tool called the MozBar, a browser extension for Chrome and Firefox. Install it, visit any website, and it shows you the DA of that page and the linking domain. You can also enter your domain directly on Moz's website at moz.com/domain-analysis and see your DA without installing anything.
The free version shows you your overall DA. If you pay for a Moz subscription (starting around $99 per month), you get more detailed reports: which sites are linking to you, which links are the strongest, and how your DA compares to competitors over time.
Keep in mind that the free tool updates less frequently than the paid version. If you check your DA on the free tool one day and see a different number the next day, it is usually because Moz updated their data, not because your site changed.
What a good Domain Authority score looks like
There is no universal "good" DA — it depends on your industry and your competitors. A new blog might have a DA of 5 to 15. A mid-size business site might be in the 30 to 50 range. Established news outlets and large companies often have DAs above 60.
The most useful comparison is not your absolute DA, but your DA relative to your competitors. If your main competitors all have DAs of 45 to 55, and you have a DA of 25, that is a signal that you are behind on link building. If you are at 50 and they are at 45, you are doing better.
Improving your DA takes time because it depends on earning links from other sites. You cannot directly increase it the way you might increase a page speed score. The only real path is to create content that other sites want to link to, and to build relationships with sites in your industry.
Why Domain Authority matters less than you might think
Many people treat DA as a ranking may provide. They see that a competitor has a DA of 60 and assume that is why the competitor ranks higher. Often, it is the other way around: the competitor ranks higher, so they get more links, so their DA is higher. The high DA is a symptom, not the cause.
If you focus only on building links to raise your DA, you might end up with low-quality links that do not help your rankings. Google has gotten better at detecting and ignoring manipulative link schemes. A site with a DA of 40 built on genuine, relevant links will often outrank a site with a DA of 55 built on paid or low-quality links.
The better approach is to focus on what actually moves rankings: creating content that people want to read and link to, making sure your site is technically sound, and earning links naturally as a result of that content being good. Your DA will follow.
Frequently Asked Questions
Does Google use Domain Authority in its ranking algorithm?
No. Google does not use Moz's Domain Authority score. Google has its own systems for measuring site authority, which they do not publish in detail. DA is a third-party prediction tool, useful for comparison but not a direct ranking factor.
Can I improve my Domain Authority quickly?
Not reliably. DA depends on earning links from other sites, which takes time. Buying links or using link schemes might raise your DA temporarily, but Google penalizes these tactics and your rankings will suffer. Genuine improvement comes from creating content worth linking to.
Is a high Domain Authority may provide to get me better rankings?
No. A high DA is correlated with good rankings, but correlation is not causation. Content quality, relevance, user experience, and dozens of other factors matter. A site with a lower DA but better content can outrank a higher-DA site with weaker content.
How often does Domain Authority update?
Moz updates DA data regularly, but the exact schedule varies. The free tool updates less frequently than paid accounts. You might see your DA change from month to month even if your links have not changed, because Moz recalibrates their model.
Should I focus on Domain Authority or on Google rankings?
Focus on Google rankings. Domain Authority is a useful diagnostic tool — it helps you understand whether you are behind competitors on links — but it is not the goal. Better rankings bring traffic. A high DA with low rankings means your link profile is strong but something else is wrong.