One of the most commonly used metrics to understand the dynamics of SEO and ranking websites is Moz Page Authority. This metric is meant to help predict the ability of a specific web page to rank in the search engine result pages (SERPs). This metric is calculated through consideration of nearly 40 different metrics—but ultimately is most influenced by the number and quality of backlinks. Page Authority (PA) is useful to help better understand how competitors are ranking, the potential benefit of certain backlinks, and to predict how likely a page is to rank in the SERPs.
Estimated Ranking Power
Page Authority is very similar to Domain Authority in how it’s calculated through consideration of backlinks and other ranking factors. The difference is that Domain Authority (DA) takes into account links and signals directed at an entire website rather than a single page. Moz’s calculation of Page Authority does not account for any onpage factors such as content quality or keyword relevancy. For this reason, the Page Authority metric is best to be used as a broadly descriptive metric—with highest predictive relevancy being found in comparison to similar webpages. For example, two websites of near-equal overall Domain Authority—each with an article about a similar keyword topic—will likely have their ranking ability separated by overall Page Authority. The one with the higher Page Authority, in many cases, will outrank the one with a lower score.
Simplifying Page Authority
Page Authority and Domain Authority work together to paint a nice broad picture of a particular webpage’s overall power. Links from websites with high DA are great on their own—but when they also have a high PA score they can be downright deadly! One of the most illustrative examples of such is when one sees a particular niche being dominated solely by really high DA websites. While this can sometimes be regarded as a signal of near-impossible competition, the majority of times it’s a signal of an easy-to-enter niche. The reason being; sites with high domain authority will outrank sites with lower domain authority until there is enough page authority built up there to overcompensate. Large sites that briefly touch on topics related to low competition keyword phrases will show up almost by default until search engines find more suitable options. In these cases, some high quality content and a handful of solid backlinks is often enough to dominate many of the internet’s most authoritative websites.
Moz’s metrics are often some of the most practical guidelines for making broad assessments of webpages. Through the combination of Domain Authority and Page Authority alone, one can build a somewhat accurate understanding of the prowess any particular website might possess. One of the most useful applications of this understanding is in identifying the most valuable backlinks for a domain. If one website has a backlink from a powerful website with high Domain Authority—such as a CNN, MSNBC, TechCrunch, or BBC—it may still get outranked by a website that has a backlink with from a lesser DA source, but with higher PA. A linke from an article with a DA score of 80 and a PA score of 5 will be a valuable asset to any backlink profile. However, it may not offer as much overall power as a link with a DA of 65 and a PA of 30. It’s a bit more complicated than simply adding the two together and seeing which has the biggest overall number—but that’s kind of how it works. Below is a quick illustration of how these metrics can help predict rankings out in the wild:
Keyword: “Most Comfortable Shoes”
This keyword search term is definitely product focused, but produces a mixed bag of results from eCommerce websites and other content-focused websites such as Buzzfeed. Generally speaking, this SERP seems to have a considerable amount of opportunity—illustrated by the somewhat odd presence of non-product pages. Below you’ll find an overview of how the Moz Page Authority Metric can help to explain this particular SERP.
Kuru Footwear is a very niche-focused website that is all about shoes. Their backlink profile is almost entirely shoe-related, and their site seems to have been well-optimized for the keyword “Most Comfortable Shoes” and similar variations. While their overall Domain Authority is somewhat on the low-end of things—their Page Authority is very solid. In this situation, their outranking of much more authoritative domains can be partially explained by their much larger amount of page rank.
Macy’s ranking with an internal page for the keyword term “Most Comfortable Shoes” with a much higher domain authority than the Kuru Footwear website, but an almost non-existent Page Authority. This is a common occurrence for many large eCommerce websites that manage thousands of products. Their top-level pages have a lot of links, maybe even their main category pages, but more long-tail sections of the website simply aren’t often prioritized.
Note: Moz sometimes returns different Page Authority scores for subdomains of websites—such as www.macys.com vs. macys.com. At the time of writing, both versions of this url were checked and found to return the same PA value of “1”.
Coming Up Short
This metric is a powerful way to make statements like “Macy’s needs to focus building links and supportive content directly to their most comfortable shoes page in order to rank better.” However, this metric should only ever be used as a general guideline. There are many occasions in which it only tells such a small portion of the story that it’s pretty much useless. Below is one such case where Moz’s Beginners SEO Guide outranks the Wikipedia SEO page for “Search Engine Optimization,” while having less powerful overall metrics.
Moz’s Beginner’s SEO Guide
One of the most popular guides to SEO is provided by the Moz SEO website under the title of Beginner’s SEO Guide—pretty explanatory right? It’s conceivable that many people looking to find out more about SEO; what it is, how it’s used, and where it all began might be interested in this page. Moz has a very authoritative website, and this page is also immensely linked to and has a robust amount of Page Authority.
Wikipedia’s Search Engine Optimization Page
Wikipedia’s page for Search Engine Optimization is a broad discussion of SEO and many related aspects such as White Hat vs. Black Hat techniques, and how it’s applied in modern marketing strategies. Wikipedia has the maximum amount of page authority possible, coming in at an even 100. Surprisingly, this page also has a larger amount of overall Page Authority as well, likely accounted for by the large number of backlinks.
Page Authority is a great way to help better understand the dynamics of a given set of SERPs when developing a keyword strategy. Finding niches where highly authoritative websites such as Macy’s are ranking well with low overall Page Rank is often a clear signal that there is room for entry from a more niche-focused competitor. This is well-demonstrated by the Kuru Footwear vs. Macy’s results for the “Most Comfortable Shoes” SERP. The usefulness of Page Authority often falls apart when examining highly-competitive SERPS where many results have similarly powerful metrics. At this point, all the other ranking factors such as backlinks, context, on-page optimization, and user interaction all come into play. The general takeaway from the two examples above is that a website selling shoes could likely enter the SERP for “Most Comfortable Shoes” without an extreme amount of difficulty, but that a new SEO Agency isn’t likely to get anywhere near the top of page one for “Search Engine Optimization.” One way to better understand these types of metrics is to abstract them out into a common real-world example, such as being like the opinions of people.
You can’t build an entire house with just a hammer and you can’t develop an effective SEO strategy while just considering Page Authority
Domain Authority is like having a lot of recognition among people in general, such as a Senator or Celebrity. Page Authority is like have a lot of recognition on a particular subject matter. For example, Wikipedia vs. Moz competing for the keyword “Search Engine Optimization” is like two Nobel Laureates debating quantum physics. They both know their shit, and it’s hard to say which one is more right than the other. Macy’s vs. Kuru Footwear on the other hand is a different tale. This is more like a Celebrity making a paid shout out in your Facebook feed vs. and artisan shoemaker being recommended by everyone you know. While the celebrity might have greater overall recognition—most people don’t consider them to be an authority on shoes. We’ve got a more in depth article on how backlinks are like digital opinions for anyone wanting to take this analogy for more of a run. Overall, Page Authority can be a great way to measure the value of individual links, identify new keyword opportunities, and spot competitor weaknesses—but shouldn’t ever be relied on too heavily. Just like you can’t build an entire house with just a hammer, you can’t develop an effective SEO strategy while just considering Page Authority.