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IPv6 Support Checker

Check whether a website has IPv6 addresses, answers over IPv6, and has IPv6 name and mail servers.

About IPv6 Support Checker

Use the IPv6 support checker after turning on IPv6 at your host or CDN, or when an audit asks whether your site is IPv6-ready. A site can have an AAAA record and still not answer over IPv6, which can leave visitors on IPv6 networks waiting for a time-out. Enter a domain and click Check.

The checker looks up the AAAA records of the domain, and of its www name when you enter the bare domain. When our server has IPv6, it then connects to the first IPv6 address on port 443, then 80, and reports the time. If it has none at that moment, the step is marked not tested rather than failed. It also counts your name servers and mail servers with IPv6 addresses. You get a score, a verdict for each point with a suggested fix where something is missing, and a table of every host with its IPv4 and IPv6 addresses. To see which address your own connection uses, open What Is My IP. Results aren't stored and the check doesn't use your daily tasks.

How to use IPv6 Support Checker

  1. 1
    Enter a domain

    Type the site's domain, such as example.com.

  2. 2
    Click Check

    The checker reads the AAAA records and tests an IPv6 connection from our server.

  3. 3
    Read the verdicts

    Each point, from AAAA records to mail servers, comes with a fix when something is missing.

  4. 4
    Check the host table

    See the IPv4 and IPv6 addresses of the website, its name servers and its mail servers.

Why use Cubfile for this

  • Site and www

    AAAA records for the bare domain and its www version, checked together.

  • Real connection test

    Connects to the IPv6 address on port 443, then 80, when our server has IPv6.

  • Name and mail servers

    Shows how many of each have IPv6 addresses.

  • Score and fixes

    A score, a verdict per check and suggested fixes for what's missing.

FAQ

IPv6 Support Checker: questions and answers

How do I know if my website supports IPv6?
It needs an AAAA record, and the server behind it has to answer over IPv6. This checker tests both, and the verdict says ready, partly ready or not reachable over IPv6.
Why does it say IPv6 reachability wasn't tested?
The connection test only runs when our checking server has an IPv6 connection. When it doesn't, the AAAA, name server and mail server checks still run, and that one step is marked not tested.
What happens if I have an AAAA record but IPv6 doesn't work?
Visitors on IPv6 networks may wait for a time-out before they reach your site. Fix IPv6 on the server, or remove the AAAA record until it works. After changing the record, a DNS Lookup for AAAA shows what resolvers now return.
Do my name servers and mail servers need IPv6?
A website can support IPv6 without them. IPv6 name servers let IPv6-only resolvers reach your DNS, and an IPv6 mail server can take mail from IPv6-only senders, so they're reported separately.
Is the IPv6 check free?
Yes. It needs no sign-up and doesn't use your daily tasks. Each visitor has an hourly allowance, higher for members and VIP, and results aren't stored.
Share IPv6 Support Checker with a friendIt runs in any browser, and they can try it without signing up.

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