Let's look at the math behind PageRank

[sharminakter]

Ultimately, SEO professionals abused PageRank and used it to manipulate page rankings. This is probably a big part of why Google removed the toolbar in 2016.

How PageRank Works
When the patent was first filed and Google's early algorithms were developed, PageRank was based on the theory that a link from one website to another acted as a vote of trust and authority.

Therefore, the more links (votes) pointing to a page, the more trustworthy it is. And the higher it should rank.

But, as the original article states, "PageRank extends this idea by not counting links from all pages equally and normalizing based on the number of links on a page."

A link is not a simple vote. The authority of a page is taken into account. A link from a PR6 page is ultimately a more authoritative vote than a link from a PR2 page.

This flow of PageRank between pages is sometimes called "link juice" by SEO specialists.


We assume that page A has pages T1...Tn that link to it (i.e., are citations). The parameter d is a damping factor that can be set between 0 and 1.
Note that PageRanks form a probability distribution over web pages, so the sum of the PageRanks of all web pages will be equal to one.

— The Anatomy of a Large-Scale Hypertext Web egypt phone data Search Engine, Sergey Brin and Larry Page

In simpler terms, the PageRank of page B is calculated by multiplying the PageRank of page A by 0.85. This is called the damping factor .

If Page B then links to Page C, Page C receives 85% of Page B's PageRank (which is equivalent to 72.25% of Page A's PageRank).

If a web page has no links pointing to it, that page does not start with a PR0, but with a PR15.

But things get even more complicated when there are more than one external links on a page. The more links on a page, the more their power is diluted.