Formats

Unfortunately, due to the lack of a global standard, WHOIS server responses have different formats and each format requires a specific parser.

Format descriptions

Routing Policy Specification Language (RPSL)

Used by: whois.ripe.net ( for domains under .e164.arpa and all RIPE handles)

The response has one to many text blocks, devided by empty lines. Lines containing a comment start with '%'. Each block shows the content of a NIC handle which can have multiple key value pairs. Some keys (e.g. 'admin-c', 'tech-c' or 'zone-c') have a NIC handle as value, which can be looked up, too. The first block of the response is the handle that was asked for, followed by additional blocks with all referenced handles if there are any. Those handles can contain more references which can be resolved with additional lookups.