Domain Check

Tells you whether or not a particular domain name can be registered

You should use Domain Check if you wish to provide a query function for .ch and .li domain names on your website or in your web application.
Domain Check tells you whether a domain name is still available or has already been registered. No other information is provided. This service was designed for automated queries. It delivers results that can be read on screen or by a computer.

Domain Check runs on the host using port 4343. You can use these details to integrate the Domain Check search function into your web application. If you use a Whois client, it should allow you to specify a port.

Example of a Domain Check search:

whois -h -p 4343

-h = host (

-p = port (4343)

A Domain Check reply looks like this:

<Reply-Code> : <visually-readable reply>


0: This domain name can not be registered.
Reason: This domain name is already registered.

The visually-readable reply can be divided up over different lines.

The following reply codes are currently specified:


Domain name can be registered


Domain name cannot be registered


Invalid enquiry (i.e. modify enquiry prior to next attempt)


Access restricted (i.e. wait a while and then try again)


Temporary server error (i.e. wait a while and then try again)

NB: The visually-readable answer sequences (strings) can be changed without prior notice. It is thus not advisable to use them in automated software.