The domain authority vs page authority question usually gets answered as if the two were rival metrics. They are not. Moz built both with the same method and simply runs it at two levels. The useful question is not which one is better, but which level your decision sits at: choosing a site, or choosing a specific URL on it.
Everything here comes from Moz’s own explainer, What Is Page Authority?, written by Miriam Ellis and edited by Jo Cameron (November 2024), plus Moz’s separate Domain Authority page. Where Moz contradicts itself, we say so and take the narrower reading.
What page authority measures
Moz’s definition: “Page Authority (PA) is a score developed by Moz that predicts how well a specific web page will rank on search engine result pages (SERP). Page Authority scores range from one to 100, with higher scores corresponding to a greater ability to rank.”
Note the verb. PA predicts. It is a model trained to correlate with rankings, not a reading taken from Google. Moz says it “uses a machine learning model to identify the algorithm that best correlates with rankings across the thousands of SERPs that we predict against”, and that it draws on “link counts and dozens of other factors (more than 40 in total).”
The factors Moz lists include:
- linking URLs, linking root domains and linking subdomains;
- MozTrust + MozRank;
- followed links and nofollowed links;
- link anchor text distribution;
- 301 and 302 status, and new vs. old links;
- top level domains (TLDs), domain names and branded mentions;
- Spam Score.
Moz’s own summary is the one to remember: “PA is a link-centric metric.” It adds that “PA does not take into consideration specific on-page elements like keyword use or content optimization.” Later the same page lists content optimisation, user experience and social signals as things that influence PA. The two statements cannot both be true, so we rely on the definition: PA is a reading of the link graph around a URL. If you want the background on why links became the proxy, our post on PageRank covers the idea Moz is modelling.
Domain authority vs page authority, side by side
Moz draws the line in one sentence: “Whereas Page Authority measures the predictive ranking strength of a single page, Domain Authority measures the strength of entire domains or subdomains. The metrics are, however, calculated using the same methodology”. PA is “calculated in the same way as Domain Authority but at the individual page level.”
| Page Authority (PA) | Domain Authority (DA) | |
|---|---|---|
| Measures | Predicted ranking strength of a single page | Strength of an entire domain or subdomain |
| Scale | 1 to 100, logarithmic | 1 to 100 |
| Built from | Moz’s web index; link counts and 40+ factors | The same methodology, at domain level |
| Good score? | “There isn’t necessarily a ‘good’ or ‘bad'” score | “No universal ‘good’ or ‘average'” score |
| Best used for | Picking which page to pitch, link from or report on | Shortlisting sites |
| Google ranking factor? | “No” | “Not a Google ranking factor” |
Because the method is shared, the two scores tend to move together but need not match. A new article on a strong domain can carry a high DA and a low PA until links point at it directly. A single heavily linked page on a modest site can show the reverse.
Why both scores are relative and logarithmic
Moz puts PA on “a 100-point logarithmic scale. Meaning it is significantly easier to grow your score from 20 to 30 than it is to grow from 70 to 80.” A ten-point gain is not a fixed amount of improvement; it depends where you start.
The scores also drift. “We constantly update the algorithm used to calculate Page Authority, so you may see your score fluctuate from time to time.” A fall after an update may say more about the model than about your links.
What counts as a good page authority score
Moz answers this twice. First: “Because it’s a comparative tool, there isn’t necessarily a ‘good’ or ‘bad’ Page Authority score.” Then, as a rough guide, “A good page authority score typically ranges from 30 to 70, depending on industry competition.” Take the second line as Moz’s loose rule of thumb and the first as the real instruction: use PA “as a relative metric to compare against other pages rather than an absolute value.” The same applies to DA, which Moz calls “a relative metric”.
Neither is a Google metric
Moz is unambiguous. “No, PA is not an acknowledged Google search engine ranking factor.” “PA is a metric invented by Moz – not a factor created or acknowledged by Google or any other search engine.” Its Domain Authority page goes further: “Domain Authority is not a Google ranking factor and has no effect on the SERPs.”
That does not make the scores useless. It makes them a proxy. Raising PA is not a goal; earning links that would also raise PA is. Third-party metrics are built differently, and Moz’s page does not compare PA with any other tool, so don’t treat a PA and another vendor’s page score as interchangeable. Our post on Domain Rating vs Domain Authority covers the cross-tool comparison, and does Domain Rating matter asks the same question of Ahrefs’ score.
When to use PA and when to use DA
Moz lists four uses for PA: competitive research, link research, internal linking and reporting. Mapped onto decisions:
- Shortlisting sites: DA. When you are deciding which domains are worth approaching at all, the site-level score is the right filter. Pair it with Spam Score so a high number on a dubious site doesn’t slip through.
- Choosing the page: PA. Once a site is on the list, PA helps you pick the URL. Moz’s own example is choosing between a page “with a PA of 49 or a page with a PA of 91” as a link source.
- Internal linking: PA. Your strongest pages by PA are the natural places to link from when you want to pass weight to new content. Our guide to internal linking for SEO covers how to structure that.
- Reporting: both, as trends. Movement over time against the same competitors is meaningful; a single number in isolation is not.
A hypothetical makes the point. Say a guest-post host on example.com has a healthy DA, but the blog category page that would link to you has a low PA because nothing links to it. A page on example.org with a lower DA but a heavily linked resource page may be the better placement. DA chose the shortlist; PA chose the page.
Using a free page authority checker
Moz’s route is its own: “Go to Moz Link Explorer”, which needs “a free Moz community account”. Run the URL you care about and the URLs of the pages ranking above it, and read the gaps rather than the absolute scores. To see the links behind those numbers, our guide on how to check backlinks covers the next step.
The limitation: PA and DA are predictions from Moz’s own index of the web, which is not Google’s. A link Moz hasn’t found doesn’t count in either score, and a link Moz counts may carry no weight with Google. Use them to compare, never to conclude.
Frequently asked questions
What is the difference between page authority and domain authority?
Page Authority predicts the ranking strength of a single page; Domain Authority measures the strength of an entire domain or subdomain. Moz calculates both with the same methodology.
What is a good page authority score?
Moz says there isn’t necessarily a good or bad score because PA is comparative. Its rough guide is 30 to 70 depending on industry competition, but compare against the pages you compete with.
Does Google use page authority?
No. Moz states PA is a metric it invented and is not a factor created or acknowledged by Google or any other search engine.
Does on-page optimisation raise page authority?
Moz describes PA as link-centric and says it does not consider on-page elements like keyword use. Links pointing to the page are what it reads.
The takeaway Use DA to choose sites and PA to choose pages, compare both only against competitors, and remember they are Moz’s link-based predictions, not Google’s view.
