Free tool

Reverse DNS (PTR) Lookup Tool

Find the hostname an IPv4 or IPv6 address resolves back to. The lookup uses a public recursive resolver that follows the reverse DNS delegation chain for you.

How this lookup works

A reverse DNS lookup asks "what hostname does this IP address resolve back to?" It is the opposite direction of a normal lookup. Reverse DNS delegation boundaries aren't predictable the way domain apexes are, so this always queries through a public recursive resolver, which already follows that delegation chain for you.

Looking up a domain name instead? Try the DNS Lookup tool.

DNS monitoring

Need to know when DNS changes again?

OneDollarDNS watches your records and alerts you when they change, so you do not have to keep checking by hand.