Google has developed an algorithm to measure the popularity of websites: PageRank. This indicator has a direct impact on the ranking of results in the search engine. Understanding how it works is essential if you are to develop a relevant SEO (Search Engine Optimisation) strategy. Find out more about its definition, its history and how it works.
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Google PageRank: definition
The search engine analyses numerous criteria to assess the quality of a site. Its main objective is to provide Internet users with the most useful results when they carry out a search. To achieve this, it has developed PageRank.
The Google PageRank algorithm rates the popularity of pages according to the number of links pointing to them. It also analyses the quality of the websites incorporating these links. If they have a high score, this improves the positioning of the pages concerned. This system, invented by Larry Page, co-founder of Google, plays a key role in website referencing.
History of PageRank
In 1998, Sergey Brin and Larry Page, the founders of Google, introduced the idea of PageRank. The concept first appeared in their article “The Anatomy of a Large-Scale Hypertextual Web Search Engine”.
PageRank was inspired by the Science Citation Index (SCI). This measured the quality of scientific articles according to the number of times they were referred to by the Institute for Scientific Information. This same principle is used by Google in its algorithm.
The developers of PageRank were also inspired by the work of Jon Kleinberg, a researcher at Cornell University. In 1996, Kleinberg suggested to IMB the creation of a ranking based on the structure of hypertext links.
In the early 2000s, PageRank was clearly visible on websites, right in the toolbar. Everyone knew their own site’s rating, as well as that of others. This element led to aberrations: SEOs began to attach crucial importance to it. They sought to obtain as many links as possible from highly rated sites, in order to increase their own PageRank. To obtain these essential links, some SEOs sought to improve their PageRank by monetising links with other sites. Google’s objective has always been to ensure the best quality results for Internet users. It has therefore decided to put an end to these practices, which undermine the relevance of its search engine. PageRank stopped being shown to the public in 2014, and the toolbar containing it disappeared in 2016.
PageRank has not been abandoned, but it is no longer displayed publicly on sites.
How Google PageRank works
To improve your PageRank, you need to understand how it works and its impact on SEO.
How does it work?
The calculation of PageRank is based on several factors:
- The number of outbound links on each page;
- The anchor text;
- The number of pages with a link pointing to a page;
- The PageRank of each linked page;
- The behaviour of Internet users (if they click on several links on the same page, for example);
- The traffic associated with the page.
In short, Google uses the PageRank of several pages to calculate the PageRank of a single page. The number of sites adding links to a page is not enough to increase its score. These sites must themselves have an excellent PageRank to have a positive effect on referencing.
Here is the basic calculation used to estimate the PageRank of a page A (indicated here as PR(A))1:
- PR(A) = (1-d) + d (PR(T1)/C(T1) + … + PR(Tn)/C(Tn))
- “d” is a value between 0 and 1.
- “T” (T1, T2, T3…Tn) is a page containing a link to A.
- “C” is the number of links leaving page A.
PageRank can also be interpreted according to the random surfer model. Imagine a web surfer browsing pages by clicking randomly on links. They might find themselves locked into a group of linked pages. They then end up going to another page outside the site. For example, out of boredom, or because they haven’t found the content they were looking for. In this case, we consider the Pagerank of a page to be the probability that the user will go to a given page at a given time. The more pages there are pointing to it, the more likely it is that the user will land on it.
What impact does it have on SEO?
PageRank is used by Google to determine the positioning of sites in search results. The exact criteria taken into account are no longer communicated, but there are more than 200, including the number of links pointing to a web page. This indicator measures the popularity of a site, and is therefore a key factor in SEO.
By optimising certain elements of a site, you increase your PageRank score. Your site ranks higher and you generate more traffic.
Can I find out my site’s PageRank?
This indicator was public until 2014, but is no longer available. So how can you find out your PageRank? Tools have been developed to calculate it. SEO platforms have also developed their own authority metrics. The result obtained may differ from that kept secret by Google, but it’s close enough to be interesting.
Here are several PageRank checkers to consider when calculating PageRank:
URL Rating (Ahrefs)
Links pointing to another website are called backlinks. The URL Rating is a metric. It measures the strength of a URL’s backlink profile. It is based on criteria comparable to the original PageRank formula.
It gives a fairly relevant view of a page’s popularity, but it needs to be weighted. It is based on the old PageRank algorithm. This has evolved considerably since then.
TrustFlow (Majestic)
TrustFlow analyses the reliability of a site: it is the trust index. To do this, it measures :
- The quality of the links and their theme.
- The number of clicks received by a page from links placed on other sites.
A high trust index reflects the authority and quality of a site. To increase this index, you need to obtain traffic generated by backlinks positioned on relevant sites.
CitationFlow (Majestic)
CitationFlow also measures the popularity of a link by counting the number of clicks obtained. Unlike TrustFlow, it does not take into account the quality of the links, but the quantity. These two tools complement each other. By using them together, you can get closer to the Google PageRank criteria.
Domain Authority and Page Authority (Moz)
Domain Authority predicts a website’s position in search engine results. It then gives an overall score for the entire domain. Page Authority works in the same way, but gives a relevance score for each page.
LinkJuice (SEMJuice)
This mixes a number of metrics from different tools, such as Majestic or SemRush. It then weights them according to their importance to provide more accurate results.
How can I improve my PageRank?
The tools mentioned above are useful for finding out your PageRank. To improve your PageRank, you need to work on your backlinks strategy and internal site meshing.
Backlinks
Backlinks play a key role in increasing a site’s PageRank. Their value lies above all in their quality. Priority should be given to backlinks from authoritative sites, even if it means having fewer of them. A netlinking strategy aims to obtain these links in order to improve a site’s PageRank, with SEO in mind.
Internal linking
The architecture of a site, the way in which the different pages are linked together, has an impact on its SEO. While obtaining quality backlinks is essential, it is just as crucial to work on internal linking. Each link placed in the content and pages has an impact on maintaining the site’s PageRank.
Optimising internal linking increases the popularity of each URL on the site. Pages with the highest traffic, such as the home page, can pass on their popularity to the others.
PageRank is a key SEO indicator. Although it is no longer possible to know the score awarded to a site by Google, there are tools that can provide a solid estimate. By working on your backlinks strategy and your internal linking, you can improve your PageRank. You benefit from better referencing. Your site will gain in popularity and generate more traffic.
3 key points to remember :
- PageRank is the name given to the ranking of pages by Google.
- This tool, which used to be public, is now confidential.
- Implementing a relevant netlinking strategy can increase a site’s PageRank.
