AAAA Record Lookup: Free IPv6 DNS Checker

An AAAA record lookup shows the IPv6 addresses a domain name points to, along with the TTL for each one. Type in a domain and the tool lists every AAAA record it finds. It is built for site owners, developers and sysadmins who need to confirm IPv6 is set up correctly before or after a DNS change.

What Is an AAAA Record in DNS?

An AAAA record is a DNS record that maps a domain name to a 128-bit IPv6 address. It is the IPv6 counterpart of the A record, which maps a name to a 32-bit IPv4 address. People often say it out loud as "quad-A."

The name comes from the size difference: an IPv6 address is four times as long as an IPv4 address, so the record type got four A's. The record type is defined in RFC 3596, and each record holds two things you will see in the results: the address and a TTL (time to live).

An IPv6 address is written as eight groups of four hexadecimal digits separated by colons, such as 2001:0db8:0000:0000:0000:0000:0000:0010. You can drop leading zeros in each group and replace one run of all-zero groups with a double colon, so the same address becomes 2001:db8::10. Both forms mean exactly the same thing.

What does the TTL mean?

The TTL is the number of seconds a resolver may keep the answer in its cache before asking again. The lookup table shows it in seconds, for example 300s. A value of 300 means about five minutes. Common choices are 300, 3600 (one hour) and 86400 (one day).

How Is an AAAA Record Different From an A Record or CNAME?

An AAAA record returns an IPv6 address, an A record returns an IPv4 address, and a CNAME returns another domain name instead of an address. A website can have both A and AAAA records at the same time, which is called dual-stack.

A CNAME is an alias, so the final address comes from whatever name it points to. If you want to compare the IPv4 side of a domain, run the same name through an A record lookup. To trace an alias, use the CNAME record checker.

How to Use the AAAA Record Lookup

You can check a domain in a few seconds with one field and one button. Follow these steps:

1. Find the Domain Name field, which shows the placeholder example.com.
2. Type the domain or subdomain you want to check, such as www.yoursite.com. If you paste a full web address that starts with https://, the tool strips the protocol and any path for you.
3. Click Lookup AAAA Records. The button changes to "Looking up..." while the query runs.
4. Read the summary line, which says how many AAAA record(s) were found for your domain.
5. Check the table below it. The IPv6 Address column lists each address and the TTL column shows its cache time in seconds.

The name needs at least one dot, so a bare word like "localhost" is rejected with the message "Please enter a valid domain name."

Worked Example: Checking a Dual-Stack Website

Say you just enabled IPv6 on a web server and want to confirm the DNS side is live. You enter shop.example.com and click Lookup AAAA Records. The values below are illustrative.

The tool reports "2 AAAA record(s) found for shop.example.com" and shows this table:

• 2001:db8:10::a with a TTL of 300s
• 2001:db8:10::b with a TTL of 300s

Here is what that tells you. Two addresses mean the name is spread across two IPv6 hosts, which is common for load balancing or redundancy. Both share a 300 second TTL, so resolvers will cache them for about five minutes. If you later change one address, most visitors will see the update within that window. The next step is to compare these addresses with your server settings and make sure each one is actually listening for web traffic.

How to Read and Act on the Results

The result is either a list of addresses, an empty result, or an error message, and each one points to a different next step.

Records found

Check that every address is the one you expect. A public website should use a global unicast address, which normally starts with 2 or 3, such as 2001: or 2600:. If you see an address starting with fe80 (link-local), fc or fd (unique local), or just ::1 (loopback), the record is wrong for a public site and will not work for outside visitors. Replace it with the server's public IPv6 address.

No AAAA records found

The tool displays "No AAAA (IPv6) records found for this domain. The domain may not be IPv6-enabled." This is not an error. It simply means the name has no IPv6 address published, so IPv6-only visitors cannot reach it directly. If your host supports IPv6, ask for your server's IPv6 address and add an AAAA record at your DNS provider.

NXDOMAIN message

If the tool says the name does not exist, the domain or subdomain is not in DNS at all. Look for a typo, an expired domain, or a subdomain you never created.

Lookup unavailable

A message that the lookup is unavailable means the answer could not be confirmed this time. It does not prove the record is missing. Wait a moment and run the lookup again before changing anything.

TTL values

A TTL between 300 and 3600 seconds is a common, balanced range. A very low TTL such as 60 is handy right before a migration but increases query volume. A very high TTL such as 86400 means mistakes take up to a day to clear from caches, so lower it ahead of planned changes.

Who Needs an AAAA Record Lookup?

Anyone who manages a domain or troubleshoots connectivity can use this check. These are the most common situations:

• Website owners confirming that a new host or CDN setup published IPv6 addresses.
• Developers debugging a site that loads on one network but times out on another, which often traces back to a broken IPv6 path.
• Sysadmins auditing records after a server move, to catch old IPv6 addresses that still point to the previous machine.
• SEO specialists running a technical audit, since a faulty AAAA record can make pages slow or unreachable for some visitors and crawlers.
• Students learning DNS who want to see a real record type and TTL.

If you want to see every record type for a name in one view, the full DNS lookup tool groups A, AAAA, MX, NS, TXT and more together.

Best Practices, Common Mistakes and Troubleshooting

Most AAAA problems come from a few repeat mistakes, and each has a simple fix.

• Publishing an address the server does not serve. Many clients try IPv6 first. If the AAAA record exists but the web server only listens on IPv4, some visitors will hit delays or errors. Only add the record after you have tested the IPv6 address directly.
• Forgetting the www name. The root domain and the www subdomain are separate names. Look up both, because one can have IPv6 while the other does not.
• Expecting a CNAME name to hold its own AAAA. If a subdomain is an alias, the IPv6 address lives on the target name. If your lookup returns nothing for an alias, check the name it points to.
• Leaving stale records. After moving hosts, delete old AAAA records. A leftover address sends a share of traffic to a dead server.
• Mixing up address families. Pasting an IPv4 address into an AAAA record or an IPv6 address into an A record is invalid. Keep each in its correct type.
• Judging too soon after an edit. A cached answer can stay visible until its TTL expires. If your change does not appear yet, wait and check how different resolvers answer with the DNS propagation checker.

Limitations and Accuracy Notes

This tool tells you what DNS publishes, not whether the server behind an address is working. A record can exist and still point to a machine that is offline or blocking IPv6 traffic. Use the lookup to verify the DNS layer, then test the site itself over IPv6.

The results reflect a single moment, and a recent change may not show yet because of caching. It also checks one name at a time, so you need to run each subdomain separately. To learn which network owns an address you find, run it through an ASN lookup, and for more utilities of this kind, browse the network and IP tools.

Enter your domain in the field above and run the lookup. In a few seconds you will know whether IPv6 is published, which addresses it uses and how long they stay cached, so you can fix anything that looks off.