DNS Lookup

IPAddress.com's DNS Lookup tool is an important part of network troubleshooting tools, and well suited as an online replacement for the popular "nslookup" command line tool that is found in operating systems. A lookup for DNS queries the Domain Name System and translates hostnames into IP addresses. It also reverses IP addresses and points them into hostnames.

Use our tool below by entering a domain, hostname, IPv4 or IPv6 address in the input field. Select a DNS resource record type (default is auto) and start the DNS lookup by clicking on the corresponding button.

Aside from the default auto setting in our DNS lookup tool, you can also choose from specific record type such as A Record / Address Record, AAAA Record / IPv6 Address Record, CNAME Record / Canonical Name Record, MX Record / Mail Exchange Record, NS Record / Name Server Record, PTR Record / Pointer Record, SOA Record / Start of Authority Record, TXT Record / Text Record. A description of each of these DNS records type can be found below.

Our advanced tool for looking up DNS also supports less frequently used records like AFSDB, ANY, APL, CERT, DHCID, DLV, DNAME, DNSKEY, DS, HIP, IPSECKEY, KEY, KX, LOC, NAPTR, NSEC, NSEC3, NSEC3PARAM, RP, RRSIG, SIG, SRV, SSHFP, TA, TKEY, TSIG.

Here are the record types for DNS shown by query type, domain, hostname, and IP address. Our checker supports a large variety of DNS record types that can be chosen from the select box above. If you leave the DNS record type selection on auto, a name server lookup will be performed for the most common DNS records depending on the input as shown here:

Advice for Troubleshooting DNS

Here are several ways you can troubleshoot DNS problems for a variety of network or connection issues. If none of these resolve your problems with DNS, try contacting your ISP for additional help.

Basic DNS Records

A Record / Address Record

The A record type is used to find the IP address(es) (IPv4) for a hostname. Thus the main use of A record lookups is to map hostnames to IP addresses, but it can also be used for other purposes like DNSBL (DNS-based Blackhole Lists).

AAAA Record / IPv6 Address Record

Similar to A record lookups, the AAAA record type looks up IPv6 addresses for a given hostname.

CNAME Record / Canonical Name Record

The CNAME record type is used to express that one hostname is an alias for another hostname (the canonical name). When an nslookup with type A or AAAA encounters a CNAME record, the query will be retried on the new hostname until the end of the CNAME chain is reached, or when an IP address for the canonical name is found.

MX Record / Mail Exchange Record

The MX record type yields a list of mail servers responsible for a given domain. Besides the hostname of the mail server the MX lookup result provides a numeric priority where the lowest number indicates the highest priority. Message delivery to mail servers should be tried in the order given.

NS Record / Name Server Record

The NS record type provides a list of name servers that are authoritative for a given domain.

PTR Record / Pointer Record

Basically the PTR record type is used to point to a location within a domain. It is most commonly used for Reverse DNS Lookups to find the hostname for an IP address.

SOA Record / Start of Authority Record

The SOA record type contains authoritative and administrative information about a DNS zone like the primary name server, the email address of the responsible administrator, and other information like serial number as well as refresh, retry, expiry and minimum TTL values.

TXT Record / Text Record

The TXT record type is used to store arbitrary descriptive text in a DNS record. This can be human-readable text or machine-readable data for mechanisms like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail) and others.

Other DNS Records

Our dnslookup tool also allows for DNS check of less frequently used DNS records like AFSDB, ANY, APL, CERT, DHCID, DLV, DNAME, DNSKEY, DS, HIP, IPSECKEY, KEY, KX, LOC, NAPTR, NSEC, NSEC3, NSEC3PARAM, RP, RRSIG, SIG, SRV, SSHFP, TA, TKEY, TSIG.
Please look at the list of DNS record types for an explanation of those resource records.