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MQTT Topic Tester
Validate topic names and filters, then visualize subscription matching without connecting to a broker.
Local routing simulation: this models topic-filter matching and optional retained delivery only. It does not model broker ACLs, QoS, subscription identifiers/options, shared-group load balancing, retained expiry, or broker-specific limits.
Published topic names
One topic per line. Empty levels such as sensors//temperature are allowed, but an entirely empty topic is not.
Subscription filters
One filter per line. + matches one level; terminal # matches remaining levels. MQTT 5 shared form: $share/group/filter.
Routing matrix
0valid topics
0valid filters
0matching routes
0invalid entries