Understanding your IPv6 test
IPv6 is the current Internet Protocol designed to replace the exhausted IPv4 address space. A good result requires more than merely having an IPv6 address.
What the score measures
The score combines IPv6-only reachability, dual-stack behavior, browser protocol preference, large-packet delivery and IPv6 hostname reachability. An IPv6 address alone does not guarantee that routes, DNS and MTU are working.
Why dual stack matters
Most of the web currently publishes both A and AAAA records. Browsers use Happy Eyeballs to race suitable routes and avoid long delays when one protocol is broken. A healthy network can use both without noticeable stalls.
MTU and PMTUD problems
IPv6 routers do not fragment packets in transit. Path MTU Discovery must work so endpoints choose a safe packet size. Misconfigured firewalls that block required ICMPv6 messages can make small requests work while larger pages stall.
How to improve a low result
Check that IPv6 is enabled on your router, install current firmware, use automatic or ISP-provided IPv6 settings, and test another network. If IPv6 is assigned but repeatedly times out, report the result to your ISP.