Google toolbar is the best seo tool ever that is used to check the pr of the site and other purposes.

If you use firefox browser then you must Add its toolbar which displays the PR and Alexa Rank of the website.

install google tool bar.
it is best.

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Calculate the value of your domain and website

The google toolbar is the only thing which is 100% accurate, but more importantly page rank has very little to do with seo so don't worry about it too much, it's important, but don't make the mistake of getting hung up on it like a lot of webmasters do.

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There are a number of tools for displaying the Google pagerank - some are better than others depending on the operating system and browser that you're running.Google's own toolbar is at: toolbar.google.com.