Page authority, PA, is a proprietary metric developed by Moz that predicts how likely a specific web page is to rank in search engine results based primarily on the strength and quality of the backlink profile pointing to that individual URL. Where domain authority measures the ranking potential of an entire domain as a unit page authority measures the ranking potential of a single page, https://example.com/specific-page: based on the links pointing specifically to that URL rather than to the domain as a whole.

Like domain authority page authority is scored on a logarithmic scale from 1 to 100, higher scores indicate stronger predicted ranking potential. The logarithmic scale means improvements become progressively more difficult as scores increase, moving from PA 20 to PA 30 requires less link acquisition than moving from PA 70 to PA 80. New pages start with low page authority, typically in the single digits, and build authority gradually as they acquire inbound links and internal link equity from the domain’s accumulated authority.

Page authority is not a Google metric, it is a third-party calculation by Moz based on their own link index and their modelling of ranking factors. Google does not use Moz’s page authority in its algorithms. However page authority and equivalent page-level metrics from other tools, URL Rating from Ahrefs, Page Score from various tools, provide useful comparative benchmarks for evaluating individual page strength, identifying link building opportunities at the page level, and assessing the relative authority of specific URLs.

Page authority vs domain authority

Page authority and domain authority measure related but distinct aspects of a site’s authority profile, understanding the difference between them is essential for using these metrics correctly.

Domain authority, DA: measures the accumulated link-based authority of the entire domain. Every backlink pointing to any page on example.com contributes to the domain’s authority calculation. DA is an aggregate signal, it reflects the overall strength of the domain as a link destination across all its pages.

Page authority, PA: measures the accumulated link-based authority of a specific URL. Only backlinks pointing directly to example.com/specific-page: and the internal link equity flowing to it from other pages on the site, contribute to that page’s PA calculation. PA is a page-specific signal, it reflects the strength of one URL as a link destination.

The relationship between DA and PA: a domain’s overall authority, DA, provides a baseline from which all pages on the domain benefit through internal PageRank distribution. High-DA domains have more authority to distribute internally, their pages start with a stronger baseline PA than equivalent pages on low-DA domains even before acquiring external backlinks.

A page on a high-DA domain with many internal links pointing to it from other high-authority pages on the same domain will have substantially higher PA than a page on the same domain that is poorly linked internally, demonstrating that PA reflects both external backlinks and internal link equity distribution.

When to use DA vs PA: domain authority is the appropriate metric when evaluating the overall ranking potential of a site, competitor analysis, acquisition decisions, domain-level link building strategy. Page authority is the appropriate metric when evaluating the ranking potential of specific pages, individual page link building, assessing the value of a specific backlink opportunity, comparing specific pages in competitive analysis.

How page authority is calculated

Moz calculates page authority using the same machine learning model framework as domain authority, trained to correlate with Google search rankings for specific pages. The inputs are focused on page-level link signals.

External backlinks to the specific URL: the number and quality of external sites linking directly to the page URL. A link to example.com/page contributes directly to that page’s authority. The quality of linking domains, their own authority, relevance, spam score, affects how much each link contributes to the page’s PA.

Internal link equity: PageRank flowing through internal links from other pages on the same domain. A page on a high-DA domain that receives many internal links from authoritative pages on the same site accumulates significant PA from internal equity distribution. The homepage, which typically receives the most external backlinks and has the highest PA on a site, distributes its accumulated authority through internal links to other pages.

Link quality and spam signals: the same quality assessment that affects domain authority applies at the page level. Links from high-quality, relevant sources contribute more to PA than links from low-quality or irrelevant sources. Spam signals in the linking pages reduce rather than increase the linked page’s PA.

Linking root domain diversity: as with domain authority diversity of linking domains matters more than raw link count. Ten links from ten different authoritative domains contribute more to PA than ten links from the same domain.

Page authority in practice

Page authority has several practical applications in SEO strategy and competitive analysis, each exploiting the page-level granularity that domain authority cannot provide.

Individual page competitive analysis: when competing for a specific search query page authority of the competing pages provides more relevant context than domain authority. Two domains may have similar DA but individual pages competing for the same query may have very different PA, revealing which specific pages have accumulated the strongest link profiles for that query. The page with higher PA from relevant, high-quality backlinks has a link-based advantage for the specific query.

Identifying high-value link building targets within competitor sites: finding the specific pages on competitor sites with the highest PA reveals where their link equity is most concentrated. These high-PA pages are the most valuable to earn links from, a backlink from a PA 70 page passes more equity than a backlink from a PA 25 page on the same domain.

Internal link equity assessment: comparing PA scores across pages on the same site reveals how effectively internal link equity is being distributed. A site where the homepage has PA 60 but important product pages have PA 25 is failing to distribute its domain authority effectively through internal linking, improving internal links to the product pages would increase their PA and ranking potential.

Evaluating specific backlink opportunities: when a link building opportunity presents itself, a site willing to link to a page, the PA of the specific page that would contain the link provides a more precise equity value estimate than the domain’s overall DA. A DA 70 site where the specific linking page has PA 20, a low-PA page on a high-DA domain, provides less direct page-level authority than a link from a DA 50 site where the linking page has PA 55.

Tracking individual page authority over time: monitoring PA for specific important pages over time, landing pages, pillar content, key product pages, tracks whether link building efforts for those specific pages are having the intended effect. Improving PA for targeted pages reflects successful page-level link acquisition.

Page authority and redirects

The intersection of page authority and redirect management mirrors the relationship between domain authority and redirects, but at the more granular page level.

PA of redirect source pages: when a page with significant PA, accumulated through external backlinks and internal equity, is redirected to a destination the PA-generating backlinks point to the source URL. A 301 permanent redirect passes the link juice from these backlinks through the redirect to the destination page, the destination page’s PA increases as it receives the equity from the source page’s backlinks.

The PA of the redirect source at the time of redirect configuration represents the link equity available for transfer. A source page with PA 45, reflecting substantial link equity, transfers more authority to the destination than a source page with PA 10, reflecting minimal link equity. PA provides a quantified estimate of the equity at stake in a redirect configuration.

Monitoring PA transfer after redirects: after configuring a redirect from a high-PA source page to a destination page monitoring the destination page’s PA over subsequent weeks and months reveals whether the equity transfer is occurring as expected. An increase in the destination page’s PA following the redirect, as Moz’s model processes the new link equity flowing through the redirect, confirms successful equity transfer.

PA of redirect destination pages: a critical consideration often overlooked. Configuring a redirect to a destination page that has very low PA, a new page with no backlinks and minimal internal links, creates a situation where the source page’s equity transfers to a weak destination. The destination page’s PA will improve through the redirect but starts from a weak baseline. Redirecting to destination pages with reasonable existing PA, established pages with some existing authority, provides a stronger foundation for the equity transfer.

Broken redirect PA waste: a redirect source page with high PA that has a broken redirect, pointing to a 404 error at the destination, wastes all the PA-generating backlinks pointing to the source. The backlinks exist and point to the source URL, but the broken redirect means no equity reaches a live destination. Monitoring redirect health and fixing broken redirects immediately recovers the wasted PA from high-value backlinks.

Page-level expired domain acquisition: when acquiring expired domains for redirect-based SEO equity recovery page-level PA analysis reveals which specific pages on the acquired domain have the highest accumulated authority. Rather than configuring only a global redirect from the acquired domain to the primary domain configuring path-level redirects from high-PA source pages to topically relevant destination pages maximises equity transfer, matching the topic of the source page’s authority to the most relevant equivalent on the destination site.

Page authority for internal pages

Internal pages, pages deeper in a site’s architecture, typically have lower PA than the domain’s homepage because they receive fewer external backlinks and less internal link equity. Improving PA for important internal pages is a key internal SEO objective.

Homepage PA as the distribution source: the homepage of most sites has the highest PA, it receives the most external backlinks, the most direct traffic, and the most internal links. The homepage distributes its accumulated PA through internal links to section pages, category pages, and individual content pages. The depth of the internal link path from homepage to any given page affects how much PA that page receives, pages accessible in one click from the homepage receive more internal equity than pages requiring five clicks.

Improving internal PA distribution: increasing the PA of important internal pages through internal linking involves adding more internal links from high-PA pages to the target pages. Adding the target page to site navigation, the header, footer, or sidebar, dramatically increases its internal link count and PA. Adding contextual links from high-PA content pages to the target page provides topically relevant internal equity. Flattening the site architecture, reducing the number of clicks required to reach important pages, increases PA for pages that were previously deep in the hierarchy.

PA for new content: newly published pages start with low PA, they have no external backlinks and minimal internal links. Accelerating PA growth for new content involves promoting the new content through internal linking from existing high-PA pages, encouraging external links through content promotion and outreach, and ensuring the new page is accessible with minimal click depth from high-traffic entry points.

Limitations of page authority

Like domain authority page authority has limitations that are important to understand for correct use.

Not a direct Google signal: Moz’s page authority is not used by Google. Ranking factors that Google actually uses, content quality, relevance, user signals, technical performance, are not fully captured in PA. A page with low PA but outstanding content and perfect technical SEO may outrank a high-PA page with mediocre content.

Link index completeness: Moz’s link index does not capture every backlink on the web. Links that Moz has not crawled are not reflected in PA calculations. This means PA may underestimate the true authority of pages with strong but less prominently discovered link profiles. Using multiple authority metrics, Ahrefs URL Rating alongside Moz PA, provides a more complete picture.

PA fluctuates: page authority changes as Moz’s link crawl discovers new links and loses track of removed links. A page’s PA may fluctuate week to week without any actual changes to the page’s link profile, the fluctuation reflects changes in Moz’s index completeness rather than genuine changes in the page’s authority.

PA correlation vs causation: high PA correlates with strong rankings but does not cause them. The underlying link quality signals that produce high PA also produce strong rankings, but simply having high PA does not guarantee rankings independent of content quality, technical health, and other factors.