IPv6 Address Record (AAAA)
Maps a domain name to a 128-bit IPv6 address — the modern successor to the A record.
Standards: RFC 3596
What is a DNS AAAA record?
AAAA records (quad-A records) map hostnames to IPv6 addresses. IPv6 uses 128-bit addresses written as eight groups of four hexadecimal digits, e.g. 2001:db8::1. AAAA records are essential for IPv6 connectivity as the internet transitions away from the depleted IPv4 address space. Most modern servers and clients support dual-stack (both A and AAAA), allowing connections over either protocol. Browsers prefer IPv6 when available via the "Happy Eyeballs" algorithm. AAAA records follow the same TTL and zone structure as A records. Many CDN providers assign AAAA records automatically alongside A records.
Record Structure
| Field | Description |
|---|---|
| Name | The hostname |
| TTL | Time to live in seconds |
| Class | IN |
| Type | AAAA |
| Address | IPv6 address, e.g. 2606:2800:220:1:248:1893:25c8:1946 |
Examples
example.com. 3600 IN AAAA 2606:2800:220:1:248:1893:25c8:1946
www.example.com. 3600 IN AAAA 2606:2800:220:1:248:1893:25c8:1946
Common Issues & Fixes
IPv6 connectivity issues for some users
Users on IPv6-only networks cannot reach the site if only an A record exists.
✓ Fix: Add an AAAA record alongside the A record for full dual-stack support.
Incorrect AAAA record causes connection timeouts
An AAAA record pointing to an unreachable IPv6 address causes Happy Eyeballs to fall back to IPv4, adding latency.
✓ Fix: Remove the incorrect AAAA record, or fix it to point to the correct IPv6 address.