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DNS Records

Search and learn DNS record types โ€” examples, when to use, RFC references

14 record types

A
Address (IPv4)RFC 1035

Maps a hostname to a 32-bit IPv4 address.

Example

example.com.    300    IN  A    93.184.216.34

When to use

Standard hostname โ†’ IPv4 mapping. Most websites have at least one A record.

AAAA
Address (IPv6)RFC 3596

Maps a hostname to a 128-bit IPv6 address.

Example

example.com.    300    IN  AAAA  2606:2800:220:1:248:1893:25c8:1946

When to use

IPv6 endpoint resolution. Modern dual-stack deployments include both A and AAAA.

CNAME
Canonical NameRFC 1035

Alias of one hostname to another. The DNS lookup follows the alias.

Example

www.example.com.   300   IN  CNAME  example.com.

When to use

Pointing subdomains (www, app) to a primary host. Cannot coexist with other records on the same name.

MX
Mail ExchangeRFC 1035

Specifies mail servers for a domain, with a priority value.

Example

example.com.    300    IN  MX    10 mail.example.com.

When to use

Required for receiving email. Lower priority = higher preference.

TXT
TextRFC 1035

Arbitrary text strings. Used for verification and policy declarations.

Example

example.com.    300    IN  TXT   "v=spf1 include:_spf.google.com ~all"

When to use

SPF/DKIM/DMARC email auth, domain verification (Google/Facebook), public keys.

NS
Name ServerRFC 1035

Delegates a DNS zone to authoritative name servers.

Example

example.com.    300    IN  NS    ns1.example.com.

When to use

Required at the apex of every zone. Lists which servers answer queries for this domain.

SOA
Start of AuthorityRFC 1035

Authoritative info about the zone: primary NS, admin email, serial, timers.

Example

example.com.   3600   IN  SOA   ns1.example.com. admin.example.com. 2026050701 7200 3600 1209600 3600

When to use

Exactly one per zone, at the apex. Required by DNS spec.

SRV
Service LocatorRFC 2782

Specifies the host/port for a service โ€” protocol, weight, priority.

Example

_sip._tcp.example.com. 300 IN SRV 10 60 5060 sipserver.example.com.

When to use

SIP/XMPP/LDAP/Minecraft service discovery. Format: _service._proto.name.

CAA
Certification Authority AuthorizationRFC 8659

Restricts which CAs can issue TLS certificates for the domain.

Example

example.com.   300    IN  CAA   0 issue "letsencrypt.org"

When to use

Prevent unauthorized CAs from issuing certs for your domain. Recommended for security.

PTR
Pointer (Reverse DNS)RFC 1035

Maps an IP address back to a hostname (in in-addr.arpa or ip6.arpa).

Example

34.216.184.93.in-addr.arpa.  300  IN  PTR  example.com.

When to use

Reverse DNS for email server reputation (spam filters), logging.

HTTPS
HTTPS Service BindingRFC 9460

Encrypted ALPN/SNI hints for HTTPS connections; supports ECH.

Example

example.com.   300    IN  HTTPS  1 . alpn="h3,h2"

When to use

Modern HTTPS optimization (HTTP/3 hint, encrypted client hello). Browser support growing.

SVCB
Service BindingRFC 9460

Generic service binding (HTTPS is a specific subtype).

Example

_dns.example.com. 300 IN SVCB 1 dns.example.com. alpn="dot"

When to use

Generic service alias with hints (e.g., DNS over TLS). Less common than HTTPS.

DS
Delegation SignerRFC 4034

DNSSEC โ€” fingerprint of child zone's KSK, stored in parent zone.

Example

example.com. 86400 IN DS 12345 13 2 ABC123...

When to use

DNSSEC chain of trust. Required when a zone is DNSSEC-signed.

DNSKEY
DNS Public KeyRFC 4034

DNSSEC โ€” public key for verifying signatures in the zone.

Example

example.com. 86400 IN DNSKEY 257 3 13 ABC456...

When to use

DNSSEC verification. Stored at zone apex; signed by KSK referenced by parent's DS.

Verify outputs before using in production. No warranty โ€” see Terms.