Voilà voilà Mr
How this test works: Your browser will be instructed to reach a series of URLs. The combination of successes and failures tells a story about how ready you are for when publishers start offering their web sites on IPv6.
Test with IPv4 DNS record
ok (1.336s) using ipv4http://ipv4.test-ipv6.com/ip/?callback=?
Fetches an object that has just an A record in DNS. This is expected to use IPv4. IPv6-only users might still reach this, if their provider has employed a NAT64/DNS64 or proxy solution.
Test with IPv6 DNS record
ok (1.133s) using ipv6http://ipv6.test-ipv6.com/ip/?callback=?
Fetches an object that has just an AAAA record in DNS. This is expected to use IPv6. Users not yet on the IPv6 Internet are likely to see this fail. As long as it fails quickly, it will be OK - for now.
Test with Dual Stack DNS record
ok (1.250s) using ipv6http://ds.test-ipv6.com/ip/?callback=?
This is the most important test. This verifies your browser can connect to a site that has both IPv4 and IPv6 records published. IPv4 only hosts should connect fine (using IPv4).
If this test fails or times out, you can expect major problems as publishers start offering their sites on IPv6.
Test for Dual Stack DNS and large packet
ok (1.164s) using ipv6http://ds.test-ipv6.com/ip/?callback=?&size=1600&fill=xxx...xxx
Validates that you can connect to a dual-stack server (like the ds test); and that you can send/receive large packets on that connection. If this test times out for any reason, it indicates trouble for World IPv6 Day.
Test IPv4 without DNS
ok (0.419s) using ipv4http://126.96.36.199/ip/?callback=?
This will try connecting with a literal IPv4 numeric address. This should work for most people, unless they are running IPv6-only. If the first test worked, but this fails, it likely confirms your provider is using NAT64/DNS64; you'll need to only try connecting using hostnames instead of numeric IP addresses.
Test IPv6 without DNS
ok (0.387s) using ipv6
This will try connecting with a literal IPv6 hexadecimal address. The primary purpose of this test is to separate out your connectivity on IPv6 from your ability to fetch DNS for it. A secondary purpose is to see if you have Teredo enabled; some systems may only use Teredo when an IPv6 address is in the URL.
Test IPv6 large packet
ok (1.069s) using ipv6http://ipv6.test-ipv6.com/ip/?callback=?&size=1600&fill=xxx...xxx
Validates that IPv6 requests with large packets work. If this test times out, but other IPv6 tests work, it suggests that there may be PMTUD issues; possibly involving IP tunnels.
Test if your ISP's DNS server uses IPv6
(This is bonus credit)
This is a test of your ISP's resolver (instead of a test of your host). If this test passes, your DNS server (often run by your ISP) is capable of reaching IPV6-only DNS authoritative servers on the Internet. This is not critical (at this time) for you to reach sites via IPv6.