Moz developed both domain authority and page authority metrics. DA and PA are the most popular SEO metrics that are used to study and evaluate the performance of websites in SERPs.
What is Domain Authority?
Moz introduced the Domain Authority score, which is used to evaluate the performance of websites in search engine ranking.
This score ranges from 1 to 100. More DA scores indicate the likelihood of a website appearing in search results.
For instance, a website having a DA 50 is likely to rank much better than a website with DA 20.
The domain authority by Moz is based on a machine learning model that recognises the sites by comparing them with already existing data of ranked websites and assigning them a score.
It is a prediction that does not guarantee that a site will definitely rank high in SERPs.
What is Page Authority?
Page Authority is a 1-100 score from Moz that predicts how well individual webpages can rank in search engines. Pages with higher scores are more likely to obtain strong SERP positions.
Like Domain Authority, Page Authority relies on machine learning algorithms rather than rigid formulas.
By examining correlations in Moz's index between ranking performance and on-page elements, the system assigns each page a ranking capability metric.
Domain Authority vs Page Authority
Moz introduced both DA and PA, and they work more or less the same.
The only difference is that DA predicts a website's ranking strength, whereas PA predicts the ranking power of individual pages in SERPs.
Both are assigned a value of 1-100 and are based on a machine-learning mechanism that has evolved over time to ensure maximum accuracy.
Moreover, both DA and PA only predict a relative likelihood of how a website or a page will perform in SERPs. It does not guarantee that a website with DA 99 will certainly appear on the top.
Domain authority and page authority algorithms consider several factors, just like search engines, to assign a ranking score to a site or web page respectively. But that does not mean it exactly imitates the search engine algorithms.
How DA and PA are measured?
Domain authority of a website is measured by tracking the number of links and root domains linking to a website.
This data is then compared with the real-world SERP data to evaluate the ranking power of a website.
Remember, this score is not consistent. It tends to fluctuate as it is based on a logarithmic scale rather than a linear one.
That means when a new data point is available, it will be added to the system; as a result, it will impact the score of all others. It will be easier for your website to grow its score from 10-20 than 80-90
This is because high DA sites with huge link profiles will occupy more space on high score levels than those with weak link profiles.
Page Authority calculations are the same as domain authority, but they are measured for individual pages.
Moz says it uses links and more than 40 other factors to calculate the PA but ignores on-page factors like keywords, content optimisation etc. Just like DA, Moz keeps updating the PA algorithm, so you may experience fluctuations in your score.
How to check DA and PA?
Since Moz is the creator of the domain authority and page authority, it is the best way to determine the DA and PA scores.
Just go to the Moz Link Explorer. It will give you 10 free trials for a month. Just insert your website link.
It will show your website's domain authority along with plenty of helpful information.
Scroll down, and you will find here the most important pages of your website, along with their page authority.
What is a good DA and PA?
Both DA and PA give relative rankings scores, so you cannot say that this score is good or bad.
To keep it simple, a good DA PA score is one that is higher than your competitors. For example, if your competitors have a DA that lies between the range of 70-80 and yours lies in a range of 50-60, that indicates your DA is not good.
On the other hand, if your competitors have a DA that ranges from 10-20, you will only be required to have a DA that is just above 20 to compete with them.
The same rule applies to PA. If your posts are about specific topics, they will only perform better if their PA is above your competitors’ posts' PA.
How to improve the DA and PA of a website?
DA is mainly related to a website’s backlink profile, so we can say that improving your link-building strategy will help you grow your DA.
But that does not mean you should ignore the other aspects of a website, i.e. quality content, user experience, and mobile friendliness. You must also focus on improving the overall SEO of your website, including technical SEO.
Write quality blog posts to attract natural backlinks, update existing content for freshness, know your competition, and make use of social media platforms to spread your word.
Just like DA, you can also improve your web pages' PA by building a strong backlink profile obtained from high-authority websites.
Is domain authority a Google ranking factor?
While surfing the internet about domain authority, you will find resources claiming DA as a ranking factor because they indicate how well a website will perform in SERPs.
So is it true?
Google doesn't use "domain authority".
In 2018, someone again asked about the existence of DA, and Mueller responded in that way:
In 2020, Mueller again denied using DA as a ranking factor.
Other than that, Google has denied the existence of DA as a ranking factor on several other occasions.
Even the creator of domain authority – Moz - has denied it and says:
Domain Authority is not a Google ranking factor and has no effect on the SERPs.
Several tools will tell you about the authority scores of your website and individual pages. But they have no impact on your website ranking.
Google has repeatedly denied they do not use DA in their algorithm to rank the websites.
In short, it is apparent neither domain authority nor page authority is a Google ranking factor.