Open DNS Resolver Checker

Open DNS Resolver Check is a tool to test if you are running an open DNS resolver on the computer or router you are connecting from. This can help identify possible security vulnerabilities.

You are about to request a DNS resolver check that may be interpreted as an 'attack' from by a firewall on your computer. Click proceed to continue with this test.

What is DNS?
DNS or Domain Name System is a method by which friendly website addresses (such as get translated into the IP address of the computer running the web site. This IP address is needed for your web browser to be able to connect to the web server. DNS is also used for e-mail amongst other things.