What is Google PageRank and How is it Calculated?

What is Google PageRank and How is it Calculated?

PageRank (yes it is spelled that way) is a link analysis system that ranks pages.  It was created by Google founders Larry Page and Sergey Brin and patented by Stanford University. A page with higher PageRank is considered to be a better match for a search term and is placed higher on the search results page.  PageRank is only one of an estimated 200 factors that Google’s search algorithm looks at when returning and ranking search results.

How is PageRank Calculated?

In a very basic sense, PageRank looks at links to the page that occur on other pages.  It doesn’t stop there, however.  PageRank also looks at the page that has the link and weighs that page for its authority for the link and the number of links on that page.

Quality of Links

English: Nodes with links in two-dimensional p...

English: Nodes with links in two-dimensional plane of PageRank and CheiRank (Photo credit: Wikipedia)

This is complicated, so look at it this way:

We are looking at the PageRank for Page A. Page A has content about Bees: buying bees, keeping bees, building beehives.

Page B has a link to Page A on it.  Page B has content about Buick Regals.  Because Buick Regals have nothing to do with bees, it has no PageRank for “bees”, therefore it has less authority and won’t contribute much to Page A‘s PageRank.  In fact, the other parts of Google’s algorithm might see this as a spam link or link farming and lower Page A‘s PageRank.

Page C is a page about honey and has a link to Page A.  This is a more authoritative link and will likely help Page A‘s PageRank.

Page D is a page about bees, and itself has a good PageRank.  If it links to Page A it will boost Page A‘s PageRank.

Quantity of Links

Each page has a certain number of PageRank points that it can pass on to the pages it links to.  “If a page with 20 PageRank points links to one other page, that one link will transfer the full amount of link juice to that one other web page. But if a page with 20 PageRank points links to five web pages (internal or external), each link will only transfer one-fifth of the link juice.” (Bruce Clay)

Keep in mind that links on a page include all links – navigation, sidebar links, image links, etc.  If you look at this page on my site, I count 26 links just in my header!  They are:

  • Logo (to the home page)
  • Mail to link
  • Facebook
  • Twitter
  • RSS
  • 21 links in my navigation

The content adds another 9 links (don’t forget to count next post and previous post links if you have them!).  The portfolio bar has 6 links (4 links + previous and next links).  The footer has 46 links!

So this very simple page has a whopping total of 87 links!  If this page had PageRank of 20 it would only pass on around .23 PageRank points to any individual page it links to.  In reality most pages are much less, only 1 or 2.  There is a PageRank checker here, but I have no idea how accurate it is.  There is also a PageRank indicator in the Google toolbar under advanced features.  The greener the indicator, the better PageRank.

The conclusion is pretty clear – it isn’t the quantity of links, it is the quality of links.

But I Need Links for User Experience!

I wouldn’t get rid of any of those links on my page; I think they are necessary for my users.  I may consider adding a rel=”nofollow” tag to the links to articles in the footer and possible some of the other links (see below for why I probably won’t bother).  This tells Google not to pass PageRank to those pages, thus saving PageRank for pages that matter.

Link Farms Will Kill PageRank

Now you can see why link farms, spammy sites that include all sorts of link with little or no content, actually will hurt your PageRank.  The page linking to your site is recognized as spammy by Google and may decrease your own PageRank.

Google penalties have caused many web owners to not only stop link building, but start link pruning instead. Poor quality links (i.e., links from spammy or off-topic sites) are like poison and can kill your search engine rankings. Only links from quality sites, and pages that are relevant to your website, will appear natural and not be subject to penalty. So never try to buy or solicit links – earn them naturally or not at all. ~Bruce Clay, What is PageRank?

Does PageRank Matter At All?

John Chow feels it doesn’t matter much in 2015:

PageRank, for most intents and purposes, just doesn’t matter all that much anymore and it seems like Google is giving PR progressively less and less weight. A site with a high PR can still easily get outranked in the search engine results page (SERP) by a site with a lower PR. And many sites that haven’t seen any meaningful update in years can still hold very high PR for some inexplicable reason.

Google, with updates like Panda and Penguin and others, has continued to shift its search algorithm to factor in other considerations. They’ve been punishing the keyword stuffers. They’ve been keying in on links where the anchor text is a little toorelevant. They’ve been paying far closer attention to social factors and how well the page is being shared. And while it seems like they’re punishing anybody that sells paid links, this doesn’t seem to be all that big a deal if the content is still relevant and provides value in more of an organic sense.

This is why I probably won’t bother adding rel=”nofollow” to any links on my page.  I’m going to concentrate on providing good, original articles and interacting with people on Twitter.  My analytics data shows a gradual rise in page views and time spent on my site and instead of trying to game my PageRank I can better spend my time doing research.

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