If you are new to DNS, please read this note on terminology. Thanks.


This tool models the route a typical DNS client takes to fetch an answer to a question. The question always consists of a domain name and a record type. There can be many different records for each domain name, for example amongst the simplest are A records to indicate that there is a corresponding IP address for the name and MX records to indicate that there is a mail host for this name. These records can co-exist with each other. Other records are more complicated, for example a CNAME cannot be present with any other record, as it says that all information for the domain name can be found elsewhere - at the canonical name.

The record types are all documented in the DNS RFC documents (1034, 1035), but here is a summary that might help you.

If you don't understand any of this, enter www.example.com and select A as the record type.

Type Description Example Notes
A A host address www.example.com This looks up the equivalent IP address(es) of the name you entered
SOA Identifies the start of a zone of authority example.com Zone boundary, typically a "domain name" in the commercial sense
CNAME Identifies the canonical name of an alias. mail.example.com This looks up the real name of this entry *
MX Identifies a mail exchange for the domain example.com This looks up the mail servers for this domain name **
NS The authoritative name server for the domain example.com This looks up the name servers for this domain name
PTR A domain name pointer This looks up the name for a given IP address. For enter
ANY Any records for the domain example.com Asks the name server to respond with everything ***

* dnscheck will indirect through CNAMEs automatically for other record types (there is an option to turn this off).
** mail clients will attempt direct delivery via an A record if there is no MX record for a domain name (RFC2821 section 5).
*** ANY queries on zone boundaries will be answered by the parent name server: dnscheck will not be referred to the delegated nameserver (which is why you see NS records and not an SOA record).

james at squish dot net