Google PageRank: what it is and why it’s still relevant
It was the algorithm that made the difference, the (first) reason why Google surpassed all of its competitors’ search engines: it was 1998 and PageRank revolutionized the way algorithms classified web pages, introducing a system capable of evaluating the importance of a site based on the “quality” of the links to it received from other sites, and not just the “number”. For years, the PageRank value associated with a page was a public reference used by SEO experts and webmasters to measure the authority of a site, but the progressive evolution of search algorithms and the abuse of manipulative practices led Google first to hide the value and then to integrate it into a broader content evaluation system. And today? The data is no longer visible, but the way it works remains an essential component of SEO, and this guide explores its mechanisms, how it has changed over time and useful strategies for interpreting it correctly, avoiding traps and false myths.
What is PageRank?
PageRank is the algorithm devised by Google to determine the authority of a web page based on the links to it from other online resources. It was the first and most distinctive classification criterion used by Google from the very beginning, and for years it was the basis of how it worked.
Developed in 1997 by Larry Page and Sergey Brin during their studies at Stanford University, the method on which PageRank is based was inspired by the way academic citations work. The idea was as simple as it was revolutionary: it’s not only the content of a page that defines its importance, but also who cites it and with what authority.
From a technical point of view, this system assigns each page a score that reflects the quality and quantity of incoming links, functioning as a sort of “popularity survey” on the web: simply put, the greater the number of authoritative links pointing to a page, the higher its value in Google’s eyes.
The way PageRank works represented a significant turning point in the world of online research and allowed Google to quickly establish itself as the most advanced search engine of its time. In the early years of the web, search engines classified sites mainly by analyzing the presence and repetition of keywords in the content, but with the introduction of PageRank, the focus shifted to a more sophisticated and meritocratic method: what a page says about itself is not enough, who talks about it and how it is talked about also matters.
For years, the algorithm was the basis of Google’s success, setting it apart from its competitors and establishing it as the search engine of choice. Today, PageRank is no longer a publicly visible value, but it has not disappeared completely: it has been integrated into Google’s various ranking systems, a sign that its underlying logic continues to influence the way the algorithm evaluates the relevance of web pages, integrated into a more sophisticated system that considers other aspects such as content quality and source reliability.
How the concept of online authority has changed
Before the arrival of PageRank, search engines used to rely on rather simple – and we can say rudimentary – systems to rank results. The most widespread method was keyword analysis: the more a word was repeated on a page, the higher the probability that the site would appear among the first search results. However, this approach was easily open to manipulation and often led to low quality results.
With the invention of PageRank, Google introduced a new criterion: the authority of a page does not only depend on internal factors (such as content), but also on external signals (the links received from other reliable sources). This made it impossible to rank well in the SERP just by aggressively repeating keywords, giving more importance to the quality of the pages rather than just text optimization.
The impact of this change was enormous: the web began to reward truly relevant and informative content, while keyword stuffing techniques lost their effectiveness. PageRank therefore paved the way for a more sophisticated SEO, in which the construction of a network of valuable links became crucial for positioning.
Why it’s called PageRank: meaning and other uses
Perhaps not everyone knows that… the name PageRank has a double meaning. On the one hand, the term refers to the concept of ranking “web pages” according to their value: this is the most immediate, literal meaning. On the other hand, it is also a direct reference to Larry Page, co-founder of Google and one of the main developers of the original algorithm.
Over time, the mathematical model on which the ranking of pages is based has inspired applications in other fields besides SEO. In the field of Natural Language Processing (NLP) and textual analysis, for example, the concept has been readapted to identify relevant keywords within large volumes of text. In this context, algorithms based on logic similar to that of PageRank are used to analyze the relationship between terms and determine the importance of individual concepts in a dataset.
The role of links in evaluating authoritativeness
PageRank is based on a key concept: not all links have the same weight. Some links transmit more value than others, and their influence on a page depends on several factors:
- The authoritativeness of the source page. A link from a site with a high PageRank will have a greater impact than one from a site of little relevance.
- The number of outgoing links on the linking page. The more external links a page has, the more the value transmitted through each link is “diluted”. In practical terms, getting a link from a page that contains few is more advantageous than one that distributes hundreds.
- The strategic use of internal links. Internal links between pages on the same site help to distribute PageRank value within the domain, optimizing navigation for users and consolidating the relevance of the most important pages.
In summary, PageRank is a method of detecting the importance, credibility and “weight” of a web page based on the type of backlink it receives. It’s a system that works in a similar way to academic citations: the stronger a backlink profile is, the more appropriate and authoritative backlinks a site receives, the greater its chances of ranking high on Google. For this reason, ever since PageRank was first adopted, the SEO community has been trying to optimize sites in relation to these values.
How does PageRank work?
The basic idea was developed by Larry Page and Sergey Brin in the Stanford laboratories, as described in their paper “The Anatomy of a Large-Scale Hypertextual Web Search Engine”. The original patent, published in 1998, made official the method by which Google orders its search results, outlining the mathematical calculations that allow it to evaluate the links between pages.
The system devised by Google to evaluate the importance of a web page is based on a probabilistic model that simulates the behavior of a user who browses by clicking on links at random.
The reference pattern is that of a “random browser” who clicks on links without a precise criterion: some pages, thanks to the links received, tend to be reached more often than others.
To simulate this process, the algorithm initially assigns the same value to all pages. Subsequently, the score is recalculated repeatedly and redistributed according to the links received until a balanced situation is reached. The end result is a rating system that establishes which contents have greater relevance on the web, rewarding those pages that receive reliable and relevant links.
The PageRank formula and the damping factor
The algorithm uses a mathematical formula that expresses the influence of a page in relation to its incoming links:
PR(A)=(1−d)+d∑i=1nC(Ti)PR(Ti)
This equation, described in the 1997 patent, means that the PageRank value of a page A depends on the links it receives from other pages T1,T2,…,Tn, each of which contributes a fraction of its own score.
More precisely, it is based on the following variables:
- PR(A) is the value of the page we want to calculate.
- d is the damping factor, a parameter generally set at 0.85, which simulates the probability that a user will continue to click on links instead of interrupting navigation.
- PR(T_i) indicates the value of the pages that link to A.
- C(T_i) represents the total number of outgoing links on page Ti.
The damping factor has an essential function in the algorithm. Without this parameter, a page could accumulate value in an unlimited way just because it receives numerous links, even if of dubious quality. To avoid this distorting effect, the damping factor redistributes a share of the total value, simulating a more realistic user behavior in which navigation does not continue indefinitely.
The studies of Taher H. Haveliwala have shown that this adjustment prevents the entire system from concentrating on a few dominant pages, instead guaranteeing a more equitable distribution of value among the various web contents. In this way, even pages with fewer direct links can emerge in the search results if supported by authority and quality signals.
How the distribution of value among links works
When a page receives value through inbound backlinks, this value is in turn transmitted through the links on the page: Google’s algorithm calculates this transmission in a proportional way, considering the total number of links and the context in which they are inserted, dividing the value of the page among all the outbound links, regardless of whether they point to internal pages of the same site or to external resources.
If a page has no outbound links, the flow of value is interrupted. If, on the other hand, it contains links, the accumulated value is distributed among them proportionally. For example, if a page receives a lot of value through authoritative backlinks and there are five outbound links on it, the transmitted value will be divided among them. The more links there are, the less value each one will transmit. Therefore, if a page with a score of 6 includes three links to other sites, each one will receive 6/3=2 units of value; if there were ten links instead, each one would receive a lower value, equal to 6/10=0.6.
The principle is that the weighting given to each link depends on both the importance of the source page and the total number of outgoing links it contains; this explains why getting a link from a page with few outgoings was more advantageous than one that contained many.
As mentioned, the logic also applies to internal links, because links to other pages on the same domain help distribute value among the different sections of a site, supporting the positioning of strategic assets. For example, a page with great authority and a good backlink profile can transfer part of its value to other pages on the site through well-organized internal links. In his studies dedicated to the mathematical analysis of PageRank, Fan Chung highlighted in particular how a well-planned internal structure can optimize the circulation of value without wasting it unnecessarily.
In the early years of Google, to exploit this logic, frequent attempts were made to obtain links from institutional pages or pages with few external links, thus maximizing the transfer of value. In SEO language, the value transmitted by links is often called link juice, although some prefer to use the expression link equity, a concept that is not limited to the amount of distributed value, but also considers determining factors such as the authoritativeness of the source page, the semantic relevance of the link and the context in which it is inserted.
A strategically structured site can make the most of its network of internal links to improve the positioning of the most relevant pages.
History and evolution of PageRank
The idea behind PageRank was conceived in 1997 in the laboratories of Stanford University, where Larry Page and Sergey Brin were studying a system to classify web pages more effectively than traditional methods. Their approach was based on a theory inspired by the academic world, in which citations between scientific articles are used to determine their relevance; in the same way, a link to a page was to be interpreted as a “vote of confidence”, an indication of the importance of the referenced content.
In 1998 Google registered the official patent for PageRank, confirming the adoption of the algorithm as a key factor for positioning in search results, and launching an innovation that, as mentioned, allowed Google to stand out from other search engines, which until that moment mainly relied on the density of keywords in the text of web pages. With PageRank, Google was able to offer higher quality results, based on the network of links rather than on simple repetitions of terms.
In the beginning, PageRank was therefore (also) an index of the popularity of a site on the web, determined by the number of backlinks received from other sites, which represented “votes” of trust and approval, which in turn had a different weight based on the value of the linking site and its popularity. On Wikipedia there is a specific entry dedicated to this topic, complete with a simplified formula for calculating PageRank.
In the early 2000s, the PageRank value of a page could be consulted by anyone using the Google Toolbar, which displayed a score from 0 to 10, thus determining the perceived authority of each website. This gave rise to numerous SEO strategies focused on obtaining backlinks from sources considered reliable, leading to the emergence of link building practices aimed at increasing the score.
Over time, Google has had to face a growing problem: the artificial manipulation of PageRank by those who built backlink networks with the sole purpose of climbing the SERP. To counter these abuses, updates were introduced that radically changed the weight of the algorithm, adding new metrics and more sophisticated levels of analysis. The last official public update of PageRank was in December 2013, and in October of the following year it was announced that the PageRank of Google Toolbar would be discontinued, with the toolbar itself being permanently removed from the browser two years later.
In 2016, Google stopped updating the public value of PageRank, making it an internal component of its ranking system that could no longer be consulted. Despite this, the concept of evaluating authoritativeness through links has remained a central pillar in SEO dynamics and in the subsequent algorithms adopted by the search engine.
The abandonment of public PageRank and the evolution of the algorithm
The downgrading of PageRank was a gradual process that began when Google noticed that more and more sites were using it instrumentally, trying to manipulate their ranking through artificial link schemes.
Over the years, the algorithm has been integrated into a wider ecosystem, in which the evaluation of a site’s authoritativeness no longer depends solely on the quantity of links obtained, but on a combination of qualitative factors. Today, PageRank is accompanied by E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness) signals, introduced by Google to ensure that content provides accurate and reliable information.
However, even though the toolbar PageRank has disappeared and the value is “hidden”, there are different indications about the architecture that was behind the metric: in 2017 Gary Illyes on Twitter confirmed that PageRank is still a ranking factor, and in April 2018 Google updated and extended the PageRank 2018 patent. This confirms that the link analysis system still exists and is still taken into consideration by Google, and that it has “only” lost its original meaning as an independent metric, because the value accumulated by links is now evaluated in combination with other elements.
The introduction of Penguin and the penalization of link spam
One of the most significant moments in the evolution of the Google ranking system was the release of the Penguin algorithm in 2012, which aimed to identify and penalize attempts at manipulation based on artificial link building strategies, such as the massive exchange of backlinks, the creation of low-quality directories and the purchase of links on a large scale.
Before Penguin, many SEO techniques were based on link schemes that allowed low-quality sites to gain visibility thanks to networks of links built ad hoc. With the addition of Penguin to the basic algorithm, Google began to actively downgrade sites that made excessive use of unnatural backlinks.
The update had a significant impact on SEO strategies: the penalties affected entire networks of sites, reducing the value of PageRank generated by unreliable sources. Google invited webmasters to remove suspicious links and introduced the tool Disavow Links in Google Search Console, allowing sites to report backlinks they did not want to be associated with.
Since then, off-page optimization strategies have had to adapt. Emphasis has been placed on the naturalness of links, favoring a model in which authority is obtained through spontaneous mentions rather than through artificially constructed schemes.
Today, Google’s algorithms are able to automatically identify and devalue poor quality links without the need for manual penalties, thus limiting the impact of link spam. However, the concept behind PageRank — that is, the importance of links as a signal of relevance — continues to influence the ranking of pages on search engines.
PageRank and SEO: why is it still relevant?
The algorithm developed by Google to measure the value of web pages is no longer an explicit reference in search results, but its underlying logic is still an integral part of evaluation systems. The idea that links can determine the authority of a page remains valid, even if today the weight of a link is defined by more complex criteria than in the past – and in general, the search engine is based on the identification of entities and the relationships between them.
Google continues to consider links as signs of trust and reliability, distinguishing those built naturally from those obtained through artificial practices. For this reason, modern SEO cannot ignore the quality of inbound links, the management of the internal link network and an acquisition strategy based on the creation of truly useful content.
Links play a central role in transferring value between pages and in consolidating the authority of a site, but not all have the same impact. A link from a relevant source, pertinent to the subject matter and inserted in a meaningful context, carries much more weight than a simple link inserted randomly or coming from a generic site. The coherence and position of the link within the source page are factors that amplify its effectiveness.
Added to this is the importance of managing the network of internal links. Distributing the value correctly among the different sections of a site allows the most strategic pages to emerge, improving their visibility in search engines. To do this, it is necessary to build a harmonious structure, where each link has a precise function and contributes to the navigability of the site and to users’ understanding of the content.
The relationship between PageRank and link building strategy
In the past, obtaining the highest possible number of links – regardless of the source, context, etc. – was considered the most effective strategy for improving positioning. However, the updating of algorithms has made it clear that it is not the quantity of links that determines the visibility of a page, but their quality and relevance.
A link transmits value based on the quality of the source site, the relevance of the content in which the link is present and the way it is inserted within the page. A link from an authoritative and thematically aligned page will have a much stronger impact than a generic link or one obtained in an unreliable context. In addition to the authority of the source, the position of the link in the content also has an influence: a link integrated in a natural way within the text of an article has a greater impact than a link placed at the bottom of the page, in a sidebar or in a secondary list.
The choice of anchor text is also important, because it must contextualize the link in a coherent way, without appearing artificial or over-optimized. The forced use of keywords in anchor texts is an outdated practice that can even reduce the effectiveness of the signal transmitted.
These aspects have made link building a more selective activity, where quality and strategy are more important than quantity. Obtaining natural mentions through valuable content, editorial collaborations and partnerships with truly similar sites is the most effective method for building a solid and long-lasting link network.
Link attributes and their impact on value distribution
With the evolution of Google’s algorithm, special attributes have also been introduced to control the value transmitted by a link. The best known is nofollow, which signals to search engines to not transfer PageRank value through a particular link.
Two other attributes of links have been added: rel=“sponsored” (used to mark paid or sponsored links) and rel=“ugc”, intended for user-generated links, such as those in blog and forum comments.
The correct use of these attributes helps to avoid actions related to unnatural links and to better model the flow of value within a site. If a page receives many links with the nofollow attribute, the direct benefit for ranking will be limited, but traffic and visibility will still remain important factors for overall growth.
Co-occurrence and co-citation: the value of indirect signals
In addition to direct links, Google uses more subtle signals to understand the authority of a page. Co-occurrence and co-citation are two concepts that have become increasingly important in advanced SEO strategies.
Co-occurrence refers to the repeated presence of a site or a key term in thematically related contexts, even without an actual link. If a brand is frequently mentioned in industry articles, the search engine may still consider it relevant to that topic.
Co-citation occurs when two authoritative sites mention the same resource, even without linking to it directly. This can help increase the perceived reliability of a page in Google’s eyes.
These elements demonstrate that in contemporary SEO it is not only the quantity of links received that counts, but also the way in which a site is contextualized within a network of relevant content.
The strategic role of internal links in the distribution of value
Although the value of a domain often depends on external links, the management of the internal link network plays an equally decisive role in consolidating the authority of the most important pages.
A well-structured site is able to intelligently redistribute the value received from external links, favoring the pages that you want to rank higher. To do this, it is essential to:
- Link the most relevant pages in the main navigation and within the content.
- Avoid orphan pages, i.e. those that do not receive any internal links.
- Use descriptive anchor text to clarify the topic of the linked pages.
Poor management of internal links can disperse accumulated value and prevent strategic pages from obtaining the right visibility in search results.
Site-wide links and redirects: optimal value distribution
Not all links have the same weight within a site. Links present on every page, such as those in the footer, sidebar or navigation menu are considered “site-wide” and transmit a lower value than contextual links present in the main content. For this reason, in the optimization strategy it is preferable to give priority to internal contextual links, limiting the excessive use of repeated references throughout the site.
Another variable to consider is the management of deleted or moved pages. If a URL that has accumulated value is removed without proper redirection management, there is a risk of losing some of the acquired value. Redirects 301 are the correct way to transfer the value of an obsolete page to a new resource, while redirects 302, being temporary, do not transmit the same ranking value.
SEOZoom’s role in link analysis
Measuring the impact of links is not always simple, especially considering that public data on PageRank is no longer available, but an effective link building strategy requires tools that allow you to evaluate the real impact of the links acquired. With SEOZoom we provide a complete system for monitoring the quality of a site’s link network, offering a series of advanced metrics that go beyond simple information about the presence of backlinks.
First of all, Zoom Authority allows you to obtain a clear evaluation of the level of authority of the domains that link to a site, analyzing not only the number of inbound links, but also the context, thematic relevance and quality of the traffic generated. This allows you to understand which links are really useful and which, on the other hand, could prove to be ineffective or even harmful. All this information contributes to the classification of inbound links in the “Backlinks” section of a project, where all these links are evaluated on a scale from “very low quality” to “very high quality”.
Furthermore, with the “Find link partners” and “Find sector partners” functions it is possible to explore useful resources within your market niche from which it could be strategic to acquire a link, just as with competitor analysis there is the possibility to study the link acquisition tactics of the main organic rivals.
FAQ: frequently asked questions about PageRank
The evolution of the PageRank algorithm has led to profound changes in the way Google evaluates web pages. Although its numerical value is no longer publicly accessible, the basic concept is still an integral part of the ranking system. Links maintain a crucial role, but their influence is measured in a more sophisticated way, considering not only quantity but above all quality.
Below, we answer the most common questions to clarify how PageRank works and its current role in SEO.
- What is Google PageRank and what is it today?
PageRank was the algorithm developed by Google to evaluate the relevance of a web page based on inbound links. Today, even if the system is no longer publicly visible, links continue to represent an important factor for ranking, although they are flanked by other criteria such as the quality of the content and the authority of the site.
- Who invented PageRank?
The algorithm was developed by Larry Page and Sergey Brin at Stanford University in 1997.
- Why is it called PageRank?
The name comes from both the concept of a web “page” and the surname of Larry Page, one of the founders of Google.
- What is the PageRank formula?
The original algorithm equation is
PR(A)=(1−d)+d∑i=1nC(Ti)PR(Ti)
Where:
- PR(A) is the value of the target page
- d is the damping factor, usually 0.85
- PR(T_i) represents the value of the pages that link to A
- C(T_i) is the number of outgoing links on each linking page
This formula calculates the theoretical value of a page based on the links it receives, distributing the score among the linked pages.
- How does the PageRank algorithm work?
The algorithm initially assigns the same value to all pages, then redistributes the score based on the links received. The recalculation process is repeated several times until the values stabilize, creating a hierarchy based on the most relevant links.
- What does PageRank measure?
It measures the “popularity” and authority of a web page, evaluating the quantity and quality of the links that point to it.
- Why is PageRank important?
When it was introduced, PageRank revolutionized the way search engines classified pages, moving away from systems based solely on keywords. Thanks to its structure, Google was able to offer more relevant results by rewarding pages with more authoritative references. Today the basic concept is still relevant, but integrated with other ranking factors that have reduced its direct influence, such as the quality of the content and the reliability of the site.
- How to measure PageRank?
In the past, the PageRank value of a page could be consulted publicly through the Google Toolbar, which showed a score between 0 and 10 periodically updated by Google. This value was calculated taking into account all inbound links, weighted according to their source value. After 2016 Google stopped publishing the exact PageRank score, but the concept is still the basis for evaluating links. Today, it is possible to estimate the “weight” of a page in terms of authority and link equity through the alternative metrics of SEO tools, which evaluate the influence of a site based on the links it receives and their quality.
- What is the PageRank score?
The score of a single page represented its relative authority compared to other web pages, determined by the number and quality of links received. The specific value of a page was updated periodically and publicly visible until 2016. Over time, Google stopped displaying it, but the underlying concept is still used in contemporary ranking systems.
- How does the PageRank range of values work?
The original PageRank assigned each page a score between 0 and 10, based on a logarithmic scale. This means that the difference between a PageRank of 3 and a PageRank of 4 was much less than the difference between a PageRank of 7 and a PageRank of 8. High-value pages transmitted more authority to outbound links.
- How is PageRank used?
Originally, webmasters could monitor the PageRank value of a page using the Google Toolbar and optimize their link building to increase it. The calculation was made using the original mathematical formula, and the main strategy was to obtain links from pages with a high value to benefit from them. Today, although no longer publicly accessible, the principle on which it is based is still used to measure the distribution of authority within a site and to plan effective link building strategies.
- Do internal links influence PageRank?
Yes, a good internal link structure helps distribute value between the pages of a site, helping to improve their relevance in Google’s eyes.
- Do nofollow links transmit PageRank?
No, links with the nofollow attribute do not transfer the direct value of a link, but they can still help increase the visibility and authority of a site in other ways.
- When and why did Google stop using PageRank?
Google stopped displaying it publicly in 2016 to prevent manipulative practices: public information on PageRank had facilitated manipulative optimization activities (including through black hat SEO techniques) and the use of spam links in order to force ranking. Despite the Penguin Update, many SEO agencies and websites continued to work only by focusing on manipulative PageRank increases, thus forcing Google to take definitive and final action. Today, however, there are still internal systems based on the algorithm and inspired by its logic.
- Why does Google keep the PageRank formula secret?
The public version of PageRank led to attempts to manipulate the results. To avoid abuse, Google stopped releasing precise details about how it worked.
- Does Google still use PageRank?
Yes, but in a more advanced form, together with other ranking signals that make the system more sophisticated and less dependent on links alone.
- What replaced PageRank?
The concept of evaluation through links has been integrated into more advanced systems, including the E-E-A-T metrics (experience, expertise, authoritativeness and trustworthiness).
- What does PageRank mean in NLP (Natural Language Processing)?
In some scientific fields, the concept of PageRank has been adapted to determine the importance of words and phrases in sets of texts, but its main use is still linked to web links.
- How do you get quality links?
Through useful content, spontaneous citations and mentions on reliable sites in your sector. Strategies such as guest blogging, digital PR and editorial collaborations can facilitate the acquisition of valid backlinks.
- What matters more: quality or quantity of links?
Quality has become the predominant factor. A link from an authoritative and relevant source has a greater impact than a large number of generic and low-quality backlinks.
* cover image from
https://www.flickr.com/photos/brentdpayne/4304054542, reworked.
