• Page Strength Checker: Gives information about any URL that let you determine the strength of a page. Age of the domain, number of backlinks and PageRank are displayed.
  • PageRank: Check the PageRank of any page at 37 Google data centers. Gives a great overview of how Google’s data centers see your PageRank.
  • SEOMoz Tools: A great collection of some very useful tools like: Back Anchor Text Analysis, Crawl text and many more.
  • Xinu: An all in one page information tool. Enter a URL and get everything you can imagine about the web page.

More tools:
http://…/the-top-15-free-seo-tools.html

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  5. Search Engine Optimization (SEO), what little I know
  6. Where Are All The Google Data Centers?
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