Free is a web based search tool used to find out if a domain name or contact identifier is available for registration or not, targeted mainly towards the .NU resellers. Given a search string, Free responds with "occupied" if the domain name or contact identifier is already registered, "not_valid" if the search string does not comply with the .NU naming convention or "free" if the name or identifier is available for registration.

Usage is: http://free.iis.nu/free?q=example.nu where "example.nu" is the domain you want to check the availability of.

The tool "free" is identical to the service DAS (Domain Availability Service) provided by other Registries.