Reverse dns lookup tool
What is this?
Reverse-dns.org provides a quick access to reverse name resolution. With this site you can translate an IP address with his hostname.
Simply fill the following form and press the "Send Query" button to see the result for your reverse dns lookup.
What is a reverse lookup?
The DNS system is delegated to translate hostnames into IP addresses to permit a quick connection between computers. The same system is also very useful to perform a reverse process: translate ip addresses into hostnames. This, also if it might be considered a secondary problem, is very important, since it's vital for some services (like Mail transport agents).
The reverse resolution process starts with an ip address, which, in our example, can be considered as X.Y.Z.K (where the four letters are a visual representation of four numbers). This ip address needs to be translated into an hostname via the DNS. DNS systems normally handle domain names and hostnames as query objects, so the IP address is translated into an hostname under the in-addr.arpa zone. The corresponding hostname is obtained reversing the four number's order and appending the main zone name: K.Z.Y.X.in-addr.arpa. This is the hostname that the DNS is queried to translate via a PTR query.
The process schema is the following
- ip address: X.Y.Z.K
- ip address in reverted order: K.Z.Y.X
- in-addr.arpa zone append: K.Z.Y.X.in-addr.arpa
- query the dns for a record PTR
At this point you can know the hostname corresponding to that IP address. (this site provides a full ip address reversion, so do not insert into the form the reverted ip, insert it in the normal octect order)