# How does the PageRank work

## PageRank

### What is the PageRank?

At the PageRank it is an algorithm from Google. This algorithm analyzes and weights the link structure of a website. The basic principle: The more high-quality links refer to a website, the higher the PageRank of this page. And the higher the PageRank, the more important the website is. However, the PageRank does not make any statement about the quality of the content of a website.

### Origin of name

The term “PageRank” does not refer to the rank that a website has in the search results, but goes back to one of the developers of the algorithm - Larry Page. Together with Sergey Brin In 1997 he developed the Method for node ranking in a linked database at Stanford University, for which a patent has been applied for - the first steps in the creation of Google, which was founded by Brin and Page. The PageRank was, so to speak, the basis for the Google search and at the same time the decisive factor for the success of the search engine.

### How PageRank works

Each page receives a PageRank value between 0 and 10, whereby it becomes more and more difficult to reach the next level upwards. With a PageRank of 0, either pages that are still new on the Internet or pages that have been downgraded by Google due to violations are rated.

The PageRank algorithm ultimately evaluates all documents in the network according to their links or the importance of their links.

The formula for this is:

PR (A) = (1-d) + d (PR (T1) / C (T1) +… + PR (Tn) / C (Tn))

Explanations:

PR (A): PageRank of a page A

PR (Ti): PageRank of the pages Ti, of which a link points to page A.

C (Ti): Number of links on page Ti

d: damping factor - 0 <= d <= 1

### Random Surfer and Reasonable Surfer Model

According to the developers of PageRank Larry Page and Sergey Brin, the calculation is based on the behavior of a random Internet surfer - the Random server. This starts its way on any page in the network and is linked to other pages. However, this does not happen indefinitely, because at some point the random user has enough and he breaks off the path - this is taken into account via the damping factor d. The probability that the surfer will reach another page via a link depends on the number of links on the page. This probability is roughly comparable to the PageRank of the site.

Nowadays, however, this random model is considered obsolete, as the user no longer clicks on links at random, but many other factors influence his behavior. It is therefore not a random server, but one Reasonable server. In the Reasonable Server model, the relevance of the content of the link and its position on the page play a role. For example, the user is more likely to click on a link if it thematically matches the page on which he is currently located and if the link is in the text instead of in the footer or in the sidebar.

### Public vs. internal PageRank

Google differentiates between external / public and internally. According to the company, the internal PageRank, which is only visible to Google, is updated regularly, while the public PageRank is or was updated only rarely and at very different intervals.

Rand Fishkin from MOZ gave a good explanation on Whiteboard Friday:

Source: What is Google’s PageRank good for? - Whiteboard Friday

### Show PageRank

In 2000, Google first published the PageRank values ​​using a toolbar for Internet Explorer. There, this website's quality rating was not only displayed as a scale from 1 to 10, but also graphically with a colored bar, green for a high, red for a low PageRank. However, the PageRank toolbar no longer exists since April 2016. There is no longer any possibility of displaying the PageRank publicly. According to Google, the PageRank is still used internally to evaluate search results.

### Pagerank update

The last Toolbar PageRank update is from December 2013. About a year later, John Mueller said that no further update was carried out after this update and that the toolbar will probably not be updated in the future:

As already described in the previous paragraph, this has also been confirmed. This means that Google will officially no longer publish updates on PageRank.

### Relevance of PageRank for SEO

Google itself emphasizes that the PageRank nowadays in rankingonly a very small role plays. While this algorithm was the basis for search results in the beginning, there are now many other factors that influence the ranking of a website and are much more relevant with regard to the user experience.

The fact that PageRank has lost a lot of its importance is certainly also due to the numerous manipulative methods used to influence it. With the introduction, a lively link buying and swapping business developed at the same time, in which the PageRank acted like a kind of currency. However, one cannot say that PageRank has been abolished either. It is only no longer relevant for today's SEO measures, since there is no current data on it anyway.