Domain IP C Class Checking Tool

Webmaster Toolkit whipped up another quick tool. His C class IP checker lets you check if two domains are on the same IP block.

It is believed that domains which are hosted on the same C block may not get as much credit for linking to one another as sites on various independ IP C block addresses.

{update: it worked when I first tried it, but one person just reported that they had a problem with it. I let Will know so hopefully it will be good to go soon.}

Whois Source is another good place to check the IP address of your websites.

Published: July 22, 2004 by Aaron Wall in seo tools


July 22, 2004 - 5:38pm


I use this tool with to URL. They have different IP Address (66.33.52.XXX and 69.93.129.CCC) but they are in the same class A. The tool reports me that these 2 URLs are in the same class C, and that is not real.

It is working good this tool?


July 22, 2004 - 5:53pm

Grr... thanks for catching that. I will go bug Will and let him know. I am sure he will get it going soon.


July 22, 2004 - 7:56pm

martin, please email me the urls you used to check and I'll take a look

July 22, 2004 - 9:02pm

Well I gave it a tweak anyway as I found something that may have been causing it.

August 31, 2008 - 1:05pm

hosts like give you the option of different ips for each domain.....i wanted to ask you does that work.......are SE's able to recognise that the ips are different but the domains are owned by the same person.
Best Regards,

September 1, 2008 - 12:25am

From what I have seen so far Google does not care if the sites are related so long as they have quality content and other link sources as well. That may change down the road though.

December 29, 2008 - 1:06pm

just saw this reply....somehow missed the notification....anyways thanks for the reply. i am switching to since i have been having prob. with my current host...they have dedicated ip domain hosting so was wondering is it is worth purchasing. donno if the websites will get any benefits from each other since they r on different ips.

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