Manual Reference Pages  - WHOIS (1)


whois - client for the whois directory service



whois [~-h~HOST~] [~-p~ PORT~] [~-aCFHlLMmrRSVx~] [~-g~SOURCE:FIRST-LAST~] [~-i~ATTR~] [~-S~SOURCE~] [~-T~TYPE~] object

whois -t TYPE

whois -v TYPE

whois -q keyword


whois searches for an object in a RFC 3912 database.

This version of the whois client tries to guess the right server to ask for the specified object. If no guess can be made it will connect to for NIC handles or for IPv4 addresses and network names.


-h HOST Connect to HOST.
-H Do not display the legal disclaimers some registries like to show you.
-p PORT Connect to PORT.
--verbose Be verbose.
--help Display online help.
Other options are flags understood by RIPE-like servers.


Please remember that by default will only search in the domains database. If you want to search for NIC handles you have to prepend a ! character. When you do this, the default server becomes

When querying for IPv4 or IPv6 networks, the CIDR netmask length will be automatically removed from the query string.

When querying for AS numbers, the program will automatically convert the request in the appropriate format, inserting a space after the string AS.

When querying for domain names and no other flags have been specified, the program will automatically add the flag -T dn.

When querying for domain names and no other flags have been specified, the program will automatically add the flag --show-handles.

RIPE-specific command line options are ignored when querying non-RIPE servers. This may or may not be the behaviour intended by the user. When querying a non-standard server, command line options which are not to be interpreted by the client should always follow the -- separator (which marks the beginning of the query string).

If the /etc/whois.conf config file exists, it will be consulted to find a server before applying the normal rules. Each line of the file should contain a regular expression to be matched against the query text and the whois server to use, separated by white space. IDN domains must use the ACE format.

The whois protocol does not specify an encoding for characters which cannot be represented by ASCII and implementations vary wildly. If the program knows that a specific server uses a certain encoding, if needed it will transcode the server output to the encoding specified by the current system locale.

Command line arguments will always be interpreted accordingly to the current system locale and converted to the IDN ASCII Compatible Encoding.




LANG When querying and english text is requested unless the LANG or LC_MESSAGES environment variables specify a Japanese locale.
WHOIS_OPTIONS A list of options which will be evalued before the ones specified on the command line.
WHOIS_SERVER This server will be queried if the program cannot guess where some kind of objects are located. If the variable does not exist then will be queried.


RFC 3912: WHOIS Protocol Specification

RIPE-223: RIPE NCC Database Documentation

Detailed help on available flags can be found in RIPE-223 or in the help file which can be obtained with the command:
whois -h HELP


The program may have buffer overflows in the command line parser: be sure to not pass untrusted data to it. It should be rewritten to use a dynamics strings library.


This program closely tracks the user interface of the whois client developed at RIPE by Ambrose Magee and others on the base of the original BSD client. I also added support for the protocol extensions developed by David Kessens of QWest for the 6bone server.


Whois and this man page were written by Marco d’Itri <> and are licensed under the terms of the GNU General Public License, version 2 or higher.

Marco d’Itri WHOIS (1) 20 December 2009
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