Meshtastic PortNum Registry: Application Port Numbers & Packet Types

The on-air application registry for Meshtastic, sourced verbatim from meshtastic/protobufs → portnums.proto (as of 2026-07-21). Behaviour that is not in the .proto (per-port ACK semantics, MQTT bridging rules) is intentionally left to the firmware docs rather than guessed here; MQTT relevance is noted only where the .proto states it.

Dec	Hex	PortNum	Range	Payload / purpose
0	0x0	UNKNOWN_APP	Sentinel	A packet from outside the mesh, in a form the mesh does not understand.
1	0x1	TEXT_MESSAGE_APP	Core (built-in, 0-63)	Plain UTF-8 text messaging — the default chat payload.
2	0x2	REMOTE_HARDWARE_APP	Core (built-in, 0-63)	Built-in GPIO / remote hardware control example app.
3	0x3	POSITION_APP	Core (built-in, 0-63)	Position updates via the Position protobuf.
4	0x4	NODEINFO_APP	Core (built-in, 0-63)	Node/user identity via the User protobuf.
5	0x5	ROUTING_APP	Core (built-in, 0-63)	Protocol control (acks, routing errors) via the Routing protobuf.
6	0x6	ADMIN_APP	Core (built-in, 0-63)	Remote administration via the AdminMessage protobuf.
7	0x7	TEXT_MESSAGE_COMPRESSED_APP	Core (built-in, 0-63)	TEXT_MESSAGE payloads compressed with Unishox2.
8	0x8	WAYPOINT_APP	Core (built-in, 0-63)	Shared map waypoints via the Waypoint protobuf.
9	0x9	AUDIO_APP	Core (built-in, 0-63)	Encapsulated Codec2 voice packets (2.4 GHz-class bandwidth).
10	0xA	DETECTION_SENSOR_APP	Core (built-in, 0-63)	Text messages emitted by detection-sensor modules.
11	0xB	ALERT_APP	Core (built-in, 0-63)	Text format for critical alerts (bypasses normal notification muting).
12	0xC	KEY_VERIFICATION_APP	Core (built-in, 0-63)	Handles public-key verification requests between nodes.
13	0xD	REMOTE_SHELL_APP	Core (built-in, 0-63)	Primitive remote shell access.
32	0x20	REPLY_APP	Core (built-in, 0-63)	A "ping" service that echoes any packet it receives.
33	0x21	IP_TUNNEL_APP	Core (built-in, 0-63)	Experimental IP-over-mesh tunnel (Python).
34	0x22	PAXCOUNTER_APP	Core (built-in, 0-63)	Paxcounter (people-counting) payloads.
35	0x23	STORE_FORWARD_PLUSPLUS_APP	Core (built-in, 0-63)	Git-style message-chain store-forward for Linux-native nodes.
36	0x24	NODE_STATUS_APP	Core (built-in, 0-63)	A short status string broadcast periodically by a node.
37	0x25	MESH_BEACON_APP	Core (built-in, 0-63)	Beacon-mode broadcast advertising text + channel/preset offers.
64	0x40	SERIAL_APP	Module (registered, 64-127)	Bridges a hardware serial (RX/TX) interface onto the mesh.
65	0x41	STORE_FORWARD_APP	Module (registered, 64-127)	Store-and-forward message persistence.
66	0x42	RANGE_TEST_APP	Module (registered, 64-127)	Range-testing module (distance/packet-loss measurement).
67	0x43	TELEMETRY_APP	Module (registered, 64-127)	Device / environment / power telemetry framework.
68	0x44	ZPS_APP	Module (registered, 64-127)	Experimental GPS-less position estimation.
69	0x45	SIMULATOR_APP	Module (registered, 64-127)	Linux LoRa-simulator application.
70	0x46	TRACEROUTE_APP	Module (registered, 64-127)	Traceroute — reveals the hop path a packet takes.
71	0x47	NEIGHBORINFO_APP	Module (registered, 64-127)	Aggregated info about a node's direct neighbours (network edges).
72	0x48	ATAK_PLUGIN	Module (registered, 64-127)	Official Meshtastic ATAK (Android Team Awareness Kit) plugin.
73	0x49	MAP_REPORT_APP	Module (registered, 64-127)	Unencrypted node info for public map apps — sent over MQTT.
74	0x4A	POWERSTRESS_APP	Module (registered, 64-127)	Automated power-testing / stress module.
75	0x4B	LORAWAN_BRIDGE	Module (registered, 64-127)	Transports LoRaWAN payloads with RF metadata.
76	0x4C	RETICULUM_TUNNEL_APP	Module (registered, 64-127)	Tunnel interface for the Reticulum Network Stack.
77	0x4D	CAYENNE_APP	Module (registered, 64-127)	Cayenne Low Power Payload (LPP) telemetry transport.
78	0x4E	ATAK_PLUGIN_V2	Module (registered, 64-127)	ATAK plugin v2 (TAKPacketV2 + zstd compression).
79	0x4F	LORA_OTA_APP	Module (registered, 64-127)	Signed firmware updates over LoRa (OTA).
112	0x70	GROUPALARM_APP	Module (registered, 64-127)	GroupAlarm alert-message integration transport.
256	0x100	PRIVATE_APP	Private / custom (256-511)	Reserved for private app development without rebuilding protobufs.
257	0x101	ATAK_FORWARDER	Private / custom (256-511)	ATAK forwarder module (libcotshrink).
511	0x1FF	MAX	Range limit	Upper bound of the PortNum allocation space (not an app).

How the ranges work

• 0-63 — core: built into every Meshtastic firmware (text, position, nodeinfo, routing, admin, telemetry lives just above at 67).
• 64-127 — modules: optional registered modules (serial, store-and-forward, range test, traceroute, ATAK, map report, LoRaWAN bridge, OTA).
• 256-511 — private/custom: use PRIVATE_APP (256) and above for your own applications; they will never clash with an official port.

Related

MeshPacket & Data field reference (the packet envelope that carries this portnum) · Meshtastic encryption & PSK model · device comparison · LoRa regional settings · Nostr event-kinds reference (the Nostr analogue of this page) · range calculator.

Credit: the PortNum enum is defined and maintained by the Meshtastic project in meshtastic/protobufs (GPL-3.0). This page is a dated, human-readable index of that file.