IPv6 Checker
Server-observed IP: 216.73.216.169
Server-observed family: IPv4
Live dual-stack reachability test
This test runs 3 rounds per IP family across 2 independent echo providers to reduce one-off failures and provider-specific outages. It also checks DNS64/NAT64 signals, classifies observed IPv6 addresses as native global, translated, or transition-based, audits whether the visible IPv6 interface identifier looks privacy-randomized or EUI-64-style hardware-derived, measures IPv6 /64 prefix stability versus interface-ID rotation so temporary privacy addresses can be separated from full-prefix churn, and now adds a browser-race style IPv4-versus-IPv6 winner analysis that simulates which family would likely win first-connection racing on the tested providers.
How to interpret
- Dual-stack: both probes succeed. Your browser can reach IPv4 and IPv6 internet paths.
- IPv4-only: IPv4 succeeds, IPv6 fails. Check router IPv6 WAN, ISP support, and VPN settings.
- IPv6-only: IPv6 succeeds, IPv4 fails. Rare setup, may break IPv4-only services without translation.
- No result: both probes fail, usually due to strict firewall, privacy extensions, captive portal, or temporary network issues.