IPv6 Reachability Test — do you actually have a working dual stack

Probes an IPv4 and an IPv6 literal endpoint directly from your browser to establish whether your network really has IPv6, and which protocol this page was served over.

IPv6 reachability running

Probing IPv4 and IPv6 literal endpoints...

This connection used

IPv4

Your address

216.73.216.227

HTTP protocol

HTTP/2

The probe fetches https://1.1.1.1/dns-query and https://[2606:4700:4700::1111]/dns-query directly by IP literal. Both are valid names on Cloudflare's public resolver certificate, so a successful TLS handshake to each proves that protocol has a working path out of your network. Serving this page over IPv6 proves your browser preferred it; the probe proves it is available at all.

Read: what IPv6 changes for you in practice

Frequently asked

Why does this page load over IPv4 when I have IPv6?

Happy Eyeballs. Browsers race both protocols and use whichever completes the handshake first, so a marginally faster IPv4 path wins even on a dual-stack network.

The IPv6 probe failed but my ISP says I have IPv6.

Check your router. Consumer routers frequently have IPv6 disabled by default, and many VPN clients block IPv6 entirely rather than tunnel it, which is a deliberate leak-prevention choice.