Is Google Using Several Algorithms at the Same Time?

    March 25, 2005

To analyze Google results on several Google data centers we have developped a free online tool called Google Data Centers Analysis Tool.

This tool allows you to search 17 Google data centers in one click and to view these 17 results in one window. You can see if the results are the same or not.

You can use this tool by typing:

  • a keyword or a keyphrase
  • a link: command
  • a site: command
  • Our tests For our analysis we have decided to use link: command . Why link: command? Because we know that Google only updates link: command results approximately once a month.

    If you do use our tool by typing you will see that there 3 “groups” of datacenters:

  • “Group A” that displays 865 results
  • “Group B” that displays 189 result
  • “Group C” that displays 217 results
  • We have tested it with several URL and found the same type of results with 3 “groups”. If you do the same test for your site, do you see the same 3 “groups”?

    As we keep track of our backlinks results over time for some of our sites, we have even noticed that one group displays the same results than in January and another group displays the same results than February.

    Our conclusions for this test:

  • One group of data centers displays results from January
  • Another group of data centers displays results from February
  • The third group displays results results for March
  • List of data centers that displays March backlinks results:

  • 216.239.37 www-va
  • 216.239.39 www-dc
  • 216.239.59 www-gv
  • 216.239.63
  • 64.233.161
  • 64.233.167
  • 64.233.171
  • 64.233.179
  • 64.233.185
  • 66.102.9 www-lm
  • 66.102.11 www-kr
  • List of data centers that displays February:

  • 64.233.183
  • 64.233.187
  • List of data centers that displays January:

  • 66.102.7 www-mc
  • 64.233.189
  • 216.239.57 www-cw
  • 216.239.53 www-in
  • (for each data center, we have used the .104 server. For example, for data center 216.239.53, we tested it on


    Why Google has decided to do this? According to several SEO, Google might test several algorithms at the same time. Other think that Google is broken (hardware or software problems with its huge index).

    We have done a similar test using keywords instead of link command but the results did not match whith what we have found with our first test… So it’s not so simple!

    To analyze several keywords rankings on several Google Data centers we have also used Agent Web Ranking (The full version of this software is free for 15 days, download and try it here).

    If you have also run similar tests, do not hesitate to share your results here!

    * The above was posted by Fabien Faceries at

    Olivier Duffez is an SEO consultant specialized on Google. Working on the Internet since 1997, he created in 2002 Web Rank Info, a free SEO resources French community (+13,000 members), and in 2003 his company Web Rank Expert. He created an online collaborative dictionary supported by and DMOZ.

    He’s giving SEO conferences in ImiTiki’s seminars and wrote a book about Google and SEO in 2004. He’s also part of the developpment team of PR Weaver and Agent Web Ranking softwares.