What it does
Test IPv6 checks a browser's access to IPv4, IPv6 and dual-stack endpoints and includes DNS and large-packet tests.
Test IPv6 asks the browser to fetch a series of IPv4-only, IPv6-only, dual-stack and large-packet resources. Comparing successes and failures can reveal partial readiness; a large-packet failure alongside working small IPv6 requests can suggest a path-MTU issue. The detailed version requires JavaScript and cross-site requests, while a simpler test offers less diagnostic pass/fail output. Its resolver IPv6 check concerns the DNS server, not just the device. The result samples those browser endpoints. Sharing the results URL reveals numeric IP addresses, and the optional contact form includes test and device details; the site advises against posting that link publicly.
Strengths
- Several reachability and large-packet checks
Watch out for
- The detailed test requires JavaScript and cross-site requests
Best for
- Investigating partial IPv6 connectivity
Sources
- Test your IPv6. (Oct 26, 2026)