This tool will let you see which hostname is returned when searching for a given IP address. It is useful if you want to verify how your reverse DNS is set. If reverse DNS is not correctly set for mail servers, for example, emails sent through them may be considered as spam by certain spam filters or major ISPs.


Why do we ask for a validation code?

The code hidden in the image (aka CAPTCHA, Completely Automated Turing test to tell Computers and Humans Apart) can be correctly interpreted by humans but not by computer programs. It helps us prevent the tool from being spammed. If you experience trouble interpreting the code, just reload the page and a new code will be displayed.


Reverse DNS Lookup Tool

Enter the IP address for which you want to see the reverse DNS (e.g: 111.111.111.111):

Please enter the characters you see in the image, in the box below it.