What are DNS record types? A list of the most common types you need to know

What is a DNS record?

DNS records are needed to convert URLs into IP addresses and connection instructions. DNS records generally include IP address, record type, and time-to-live or DNS TTL values, which tell the DNS resolver how long to cache a query before requesting a new one. The DNS cache, therefore, keeps a record of your online activity and should be occasionally flushed to protect your privacy and security.

What are DNS record types?

DNS records come in different types, which store different information. There are dozens of DNS resource record types that provide important information about a domain, though many are now obsolete. These different records are stored on the DNS server. When a device sends a DNS query, it gets a response from those records using special commands the server can comprehend.

List of DNS record types

The nine most common DNS record types that you’ll run into often are:

• A (IPv4 address)
• AAAA (IPv6 address/Quad A)
• CNAME (Canonical name)
• MX (Mail exchanger)
• NS (Name server)
• PTR (Pointer)
• SOA (Start of authority)
• SRV (Service location)
• TXT (Text)

Let’s look at the examples of each of these different DNS record types in more detail below.

A record

The DNS A record type is an address record and works as a translator. Its function is to map human-readable domain names into 32-bit IPv4 addresses, as in the example below.

AAAA record

DNS AAAA record, also known as “quad A,” also works as a translator. However, quad A maps fully qualified domain names onto alphanumeric 128-bit IPv6 addresses as the internet goes through a global transition from IPv4 to IPv6.

CNAME record

The “C” in the CNAME record stands for canonical, and this record redirects one domain to a different domain. When a company owns multiple domain names but wants to direct all traffic to its main site, it will use a CNAME record to direct a user’s browser to redirect from a different domain it owns to its main site.

MX record

MX stands for mail exchanger. This record stores domain names of mail servers to map where to deliver mail for a domain. The MX record follows the SMTP protocol to send emails between networks.

NS record

The name server record gives a list of the name servers that are authoritative for a domain. The DNS NS record tells browsers where they can find the IP address for a domain.

PTR record

The DNS PTR record is the pointer record and is like the reverse of the A and AAAA address records. It maps IPv4 and IPv6 addresses back to domain names.

SOA record

The start of authority, or SOA, record stores administrative information about a domain or zone, like the administrator’s email address, the zone’s serial number, and the primary authoritative name server.

SRV record

The DNS SRV record defines which host and port must be used by specific services at an IP address, like messaging or voice-over IP.

TXT record

The TXT record provides descriptive information in text format and may be used to verify domain ownership.

What are other less common types of DNS records?

Some other less common DNS record types to know about include:

• DNAME: Creates aliases for all of a domain’s subdomains.
• CERT: Stores certificates and certificate revocation lists.
• DHCID: Stores dynamic host configuration protocol (DHCP) information.
• HIP: Encrypts host identifiers.
• RP: Stores email addresses of responsible persons for a domain.
• NSEC: Links to the next record in the DNSSEC sorting order.
• LOC: Location record gives geographical information of hosts and networks.
• HINFO: Stores information about the hardware and OS used by the host.
• NAPTR: Naming authority pointer stores dynamic rules for processing requests.