AAAA
IPv6 Address Record
AAAA records map hostnames to IPv6 addresses. Learn how IPv6 mail servers, SPF ip6:, and PTR records work together for email deliverability.
Published · Last verified · Maintained by TamingDNS
AAAA
Address & Routing
RFC 3596
Yes
AAAA <ipv6-address>
AAAA 2001:db8::1
3600 s; match your A record TTL for consistency
💬 What This Record Does
An AAAA record maps a hostname to an IPv6 address, the modern successor to IPv4. As internet infrastructure moves to IPv6, mail servers that send from IPv6 need AAAA records. IPv6 sending IPs must also have PTR records (in the ip6.arpa zone) for FCrDNS checks, and SPF records must explicitly authorise IPv6 sending IPs using the ip6: mechanism.
Common Uses
- Publishing the IPv6 address of a mail server that sends from IPv6
- Dual-stack mail server configurations that support both IPv4 and IPv6
- The forward-resolution half of an IPv6 FCrDNS check
⚠️ Watch Out For
- SPF does not automatically cover IPv6 addresses. You must add explicit ip6: entries.
- Some spam filters treat IPv6-sending IPs with extra scrutiny as IPv6 reputation data is less mature.
- Ensure your IPv6 PTR records are set (by your hosting provider) before enabling IPv6 sending.
🔧 Related Tools
📋 Complete Example Records
Whole records in zone-file form: name, TTL, class, type, then the data. Most DNS panels ask for the pieces separately. Look them up live with the DNS Lookup tool.
mail.example.com. 3600 IN AAAA 2001:db8::10
An IPv6 address record. Publishing one gives senders a second route to the host, so mail can arrive over IPv6 from that point on.
mail.example.com. 3600 IN A 192.0.2.10 mail.example.com. 3600 IN AAAA 2001:db8::10
Dual stack, with both records on one name. A sender picks between them, so both addresses need authorising in SPF and both need reverse DNS.
example.com. 3600 IN TXT "v=spf1 ip4:192.0.2.10 ip6:2001:db8::10 -all"
The SPF record that has to accompany the pair above. An ip4 term never covers an IPv6 sender, so publishing AAAA without ip6 breaks your own mail.
0.1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa. 3600 IN PTR mail.example.com.
The matching reverse record, which your hosting provider sets. IPv6 reputation data is thinner than IPv4, so some filters give an IPv6 sender without one extra scrutiny.