Here is something that’s always misunderstood – Website Ranking!
I won’t pretend to know exactly what’s going on at Google or Alexa but I will tell you what I do know about the ranking systems and it goes like this:
Google PageRank (PR)
There are two types of Google PR, “toolbar PR” and the actual PR that is given to each site. Actually, they are not two different “types” of PR, let me explain…
The Google Toolbar PR is what we see in the Google Toolbar, if you have it installed and enabled, that shows a reading of that particular pages rank, as seen by Google. This is supposedly a reading of the actual PR and it’s updated roughly every 3 months or so. (Updates normally take place every 2 to 4 months.) However, it isn’t an accurate reading of a sites authority on a page by page basis in most cases, although it can be useful when looking at the average toolbar pagerank of a range of pages!
The actual PR is updated very frequently. I couldn’t begin to tell you exactly when it’s updated, nor could anyone else other than a select few at Google, but it’s updated much more frequently than the toolbar PR.
Many new marketers believe that when the toolbar PR updates their sites will either gain visitors or lose visitors. This is simply not true.
The only update that Google does that will increase or decrease your site visitors is their algorithm updates, which are done just about every day. The algorithm is the extremely complex formula that Google uses to rank Website pages. Also, each page within a Website is looked at, not the Website as a whole.
But, how your site pages rank once they do an algorithm update will be determined by the actual PageRank of each individual page.
Alexa Traffic Ranking
This is the ranking that is provided by Alexa.com. This is based on the actual traffic going to a Website whereas Google PR is calculated mainly by the number and quality of inbound links to a specific page and not traffic.
The ranking is done with numbers as the Website with the most traffic on the Internet (currently Yahoo) would have a traffic ranking of 1 and those with very little traffic would be in the millions.
The Alexa traffic ranking has a reputation for being inaccurate. But, generally a Website with an Alexa traffic ranking of 50,000 or less receives quite a bit of traffic.
The Alexa ranking is based off the figures they collect from those who have their toolbar installed. This is why you’ll notice many technology and Internet Marketing related sites with higher Alexa rankings. It’s another reason why it’s known to be inaccurate. However, I would look at a sites Alexa ranking as a sign of authority before I would look at a pages toolbar PR as a sign of authority.