📡 MQTT Topic Matcher

Test MQTT subscription filters against sample topics. Supports + (single-level) and # (multi-level) wildcards per MQTT 3.1.1 / 5.0. 100% client-side.

Topic filter (subscription)

Topics to test (one per line)

Matches

Rules

• + matches exactly one topic level (e.g. a/+/c matches a/b/c but not a/b/d/c).
• # matches zero or more levels but must be the last character (e.g. a/# matches a, a/b, a/b/c).
• Topics starting with $ (like $SYS/...) must not match # or + at the first level per MQTT spec.
• Filter cannot be empty, contain +/# within a level, or place # anywhere but the last level.