Domain authority is a score from 1 to 100 that predicts how well a website will rank in search results
Domain authority (DA) is a number that search engines and SEO tools use to estimate how trustworthy and visible a website is. A higher score means the site is more likely to rank well when someone searches for related topics. The score ranges from 1 to 100, and it updates roughly once a month.
Domain authority is not a Google metric — Google does not publish these scores. Instead, companies like Moz and Ahrefs created domain authority as a way to predict Google's rankings based on patterns they observe. Think of it as an educated guess about how Google sees a website, not an official grade from Google itself.
You check domain authority using free or paid tools. The most common free option is the Moz toolbar, which shows DA for any website you visit. Paid tools like Ahrefs, SEMrush, and Moz's full platform show more detail about why a site has its score and how it compares to competitors.
Key Takeaways
- Domain authority ranges from 1 to 100 and updates monthly; higher scores predict better search rankings, but the score is an estimate, not an official Google rating.
- Free tools like the Moz toolbar show domain authority when ready for any website, while paid tools like Ahrefs and SEMrush reveal the reasons behind the score.
- A website's domain authority depends mainly on the number and quality of other sites linking to it, not on content quality or how new the site is.
- Domain authority for a single page (page authority) differs from the whole website score and matters more for ranking a specific article or post.
- Comparing your site's domain authority to competitors in your industry helps you understand whether your search visibility is improving or falling behind.
How to check domain authority with free tools
The fastest way to check any website's domain authority is the Moz toolbar. Install it as a browser extension for Chrome or Firefox, then visit any website. The toolbar shows the domain authority in the top right corner of your browser. No account is required, and the information updates in real time as you browse.
If you do not want to install a toolbar, you can use the Moz Domain Authority Checker on Moz's website. Type or paste the domain name into the search box, and the tool returns the DA score along with a few other metrics. This method works on any device and does not require an extension.
Both free options show only the domain authority number itself. They do not explain why the score is what it is or how it changed over time. For that information, you need a paid tool or a more detailed free report.
What domain authority actually measures
Domain authority is built almost entirely on backlinks — links from other websites pointing to your site. A website with many backlinks from trusted sources gets a higher DA score than a new site with few or no backlinks. The quality of those backlinks matters more than the quantity; a link from a major news outlet counts for far more than a link from a small blog.
Domain authority does not measure content quality, user experience, page speed, or how recently the site was updated. A website with poor writing and slow pages can have high domain authority if many reputable sites link to it. Conversely, a site with excellent content and fast loading times may have low domain authority if few other sites know about it.
This is why domain authority is useful for predicting search rankings but not a complete picture of website quality. Google's algorithm considers hundreds of factors beyond backlinks, but backlinks remain one of the strongest signals of trustworthiness.
The difference between domain authority and page authority
Page authority (PA) is a separate score that applies to a single page or post on a website, not the entire domain. A website might have a domain authority of 45, but an individual article on that site could have a page authority of 32 or 58, depending on how many backlinks point directly to that page.
Page authority matters more when you are trying to rank a specific article or product page. If you write a blog post and want it to rank for a particular search term, the page authority of that post is more relevant than the domain authority of your whole site. However, a higher domain authority makes it easier for new pages to rank because the site as a whole is more trusted.
Most free tools show only domain authority. To see page authority for individual pages, you typically need a paid tool like Ahrefs, SEMrush, or Moz's full platform.
How to use domain authority to compare websites
Domain authority is most useful when you compare it across websites in the same industry or niche. If you run a local business website and your domain authority is 15 while your main competitor's is 38, that gap tells you they likely rank higher for most searches in your area. This comparison helps you understand whether your search visibility is competitive or whether you need to focus on building more backlinks.
To compare fairly, check the domain authority of your site, your top three competitors, and a few industry leaders. Write down the scores and check them again in three months. If your score is rising and your competitors' scores are flat, you are gaining ground. If your score is flat while competitors rise, you are falling behind.
Remember that domain authority is one signal among many. A competitor with higher DA might rank better for some searches but not others. Use DA as a starting point for understanding the competitive landscape, not as the only metric that matters.
Why domain authority changes and how often to check it
Domain authority updates roughly once a month because Moz and other tools recalculate scores based on new backlink data. When a major website links to you, your DA may jump up in the next monthly update. When you lose backlinks (because a site removes a page or deletes a link), your DA may drop slightly.
You do not need to check domain authority more than once a month. Checking weekly or daily will show you the same number and waste your time. Set a calendar reminder for the first of each month to check your site and your competitors' sites, then compare the trend over several months.
A single-month change in domain authority is usually not significant. A website's DA might fluctuate by 1 or 2 points from month to month due to how the algorithm processes new data. Look for trends over three to six months to see whether your efforts to build backlinks are actually working.
Free and paid tools for checking domain authority
| Tool | Cost | What You Get |
|---|---|---|
| Moz Toolbar | Free | Domain authority and page authority as you browse; no explanation of why the score is what it is. |
| Moz Domain Authority Checker | Free | Domain authority for any website; no account needed; limited historical data. |
| Ahrefs | Paid ($99–$999/month) | Domain rating (Ahrefs' version of DA), backlink sources, page-level metrics, and competitor analysis. |
| SEMrush | Paid ($120–$450/month) | Authority score, backlink analysis, traffic estimates, and keyword rankings. |
| Moz Pro | Paid ($99–$599/month) | Domain authority tracking over time, backlink analysis, keyword research, and rank tracking. |
Frequently Asked Questions
Does domain authority affect my search rankings directly?
Domain authority does not directly affect rankings — it is a prediction tool, not a ranking factor. Google does not use Moz's DA score. However, the factors that create high domain authority (quality backlinks and site trustworthiness) do affect rankings. So a site with high DA is likely to rank well, but the DA score itself is not what Google reads.
Can I improve my domain authority quickly?
Domain authority improves slowly because it depends on backlinks from other websites, and building those takes time. You cannot buy domain authority directly. The fastest way to improve it is to create content worth linking to, reach out to relevant websites and journalists, and earn backlinks through genuine relationships and high-quality work. Expect to see meaningful changes over six months to a year.
What is a good domain authority score?
A good domain authority score depends on your industry and how long your site has existed. A new site with DA 10 is doing well; an established site with DA 20 may be underperforming. Compare your score to direct competitors in your niche. If you are within 5 points of the top-ranking sites in your industry, you are competitive.
Is domain authority the same as Google PageRank?
No. Google PageRank was an official Google metric that the company stopped publishing in 2016. Domain authority is a separate metric created by Moz to estimate trustworthiness. They measure similar things (how trusted a site is), but they are different systems and use different data.
Should I worry if my domain authority drops by 1 or 2 points?
No. Small monthly fluctuations of 1 to 3 points are normal and usually not meaningful. Focus on the trend over three to six months. If your DA drops 5 or more points and stays down, investigate whether you lost major backlinks or whether a competitor in your space gained significant new links.