Free engineer tool

NAT Type Test

Detect whether your NAT is cone or symmetric. That is the difference between WebRTC connecting peer-to-peer and needing a TURN relay. Compares your mapped address across two STUN servers, in your browser. No signup required.

Network path

NAT type

Whether this network keeps one public port for one local socket. Two STUN servers, one candidate each; if the mapped ports agree the NAT is cone, if they differ it is symmetric.

Not run yet
NAT type
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Mapped addresses
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WebRTC
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No measurement yet. Six seconds at most. No account needed.

Your runs of this tool

SRT in caller mode and WebRTC both need a NAT that keeps the mapping. A symmetric NAT needs TURN or a listener on the far side.

What to do next

Test the next thing

NAT behaviour is a property of the network you are on, not your encoder. Worth knowing before load-in, not during it.

TURN Test. Verify TURN server reachability for WebRTC and remote-director workflows.

Run TURN Test

The rest of the toolbox

11 free tests grouped by the job you arrived with: your connection, the network path, the stream setup, the programme timing.

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