IPv4 & IPv6 Connectivity Testing
Understanding how we perform real-time network protocol testing
How Real-time IPv4 and IPv6 Connectivity Tests Work
Our connectivity testing system performs genuine IPv4 and IPv6 checks by making direct connections to dedicated endpoints that are specifically configured for each protocol.
IPv4-Only Endpoint
We maintain a dedicated endpoint at ipv4only.breathtechnology.co.uk that:
- Only responds to IPv4 connections
- Returns the client's IPv4 address in HTTP headers
- Does not have AAAA DNS records (IPv6 addresses)
- Provides geolocation data derived from the connecting IP
IPv6-Only Endpoint
Similarly, we have an IPv6-only endpoint at ipv6only.breathtechnology.co.uk that:
- Only responds to IPv6 connections
- Returns the client's IPv6 address in HTTP headers
- Does not have A DNS records (IPv4 addresses)
- Provides geolocation data derived from the connecting IP
Important Note About DNS64
If you're using DNS64/NAT64 translation (common in some mobile networks), you might see an IPv4-mapped IPv6 address for the IPv4-only endpoint. This is normal behavior of DNS64, which synthesizes IPv6 addresses for IPv4-only hosts. It doesn't mean you have native IPv4 connectivity.
Technical Implementation
How we detect and verify your network protocols
Connection Detection
When you run the test, your browser makes simultaneous requests to both endpoints:
Protocol Verification
- If the IPv4 request succeeds, we receive your IPv4 address in the response headers
- If the IPv6 request succeeds, we receive your IPv6 address in the response headers
- We can determine if you're dual-stack, IPv4-only, IPv6-only, or have no connectivity
Security Considerations
All connections are made over HTTPS with strong encryption. We never store your IP addresses or any personal data. The entire process is ephemeral and privacy-focused.
Privacy First
We believe in transparency. Unlike many network testing services, we don't track, store, or monetize your connection data. Everything is processed in real-time and discarded immediately.
Try It Yourself
See the real-time connectivity testing in action:
Run Connectivity TestThe test takes less than 2 seconds and provides immediate results.