Everyone knows that pagerank (PR) increase is very unpredicatable. It is easy to get PR3. But, to get PR4 we need work on link building equally. We need an enourmous amount of incoming PR juice that increases exponentially to step up each level. But, no one actually knows how to calculate pagerank. It involves many many factors that sums up with page rank. Google might be referring to some real PR value that represent PR1-10 on PR toobar. It can be Base 2, Base 5, Base 10, Base 20, Base 50, Base 100, etc. Let us give an example of Base 10 here.
Real PR —————————–> Toolbar PR
0-9 ———————————> 0
10-99 ——————————-> 1
100-999 —————————–> 2
1,000-9,999 ————————–> 3
10,000-99,999 ————————> 4
100,000-999,999 ———————-> 5
1,000,000-9,999,999 ——————> 6
10,000,000-99,999,999 —————-> 7
100,000,000-999,999,999 ————–> 8
1,000,000,000-9,999,999,999 ———-> 9
10,000,000,000-99,999,999,999+ ——> 10
For example, if a page have PR3 and total outbound links (dofollow and nofollow) are 10 links. Assuming this PR3 page have min real PR value (1,000). Each outbound link will get 100 real PR (1,000 / 10) points added. The real PR value for nofollow links will get flushed away. So, it doesn’t matter how many dofollow/nofollow links a page have, the real PR value divided equally.
One more example of a PR8 page (assuming minimum real PR value is 100,000,000) and this page giving out 100 outgoing links (both dofollow/nofollow). Each outgoing links will carry (100,000,000 / 100) 1,000,000 real PR value. This can get at least PR6 (min 1,000,000 real PR) if we follow this chart.
Of course there are other measurent like content relevancy, anchored keyword, etc involved. Basically, relevant contents tends to give more value to our backlinks. That does not mean that irrelevant links will not give any value. Only, the value of backlink from irrelevant links are not as high as relevant links. In google’s eye, a dofollow backlink is still count as backlink.
This can be a guide to predict next pagerank too. Let’s take for example, Atniz dot com have PR3 now. I’m targeting to get PR4 in next update. Assuming, I’m at min real PR level (1,000 real PR), I need to get 9,000 real PR value in order to get PR4 (10,000 real PR). That is 10 times real PR value there. It means, I need work 10 times more on building backlinks to get one step ahead. Luckily, we have a shortcut to it from high PR dofollow blog commenting service.