# dotnet/MQTTnet

MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker). The implementation is based on the documentation from http://mqtt.org/.

Repository: https://github.com/dotnet/MQTTnet
Canonical: https://ross.abutalabs.com/products/mqttnet
Language: C#
License: MIT
License Family: permissive
Topics: mqtt, mqtt-client, mqtt-broker, mqtt-server, netcore, net, iot, iot-platform, iot-framework, csharp, netframework, communication, mqtt-protocol, nuget, broker, tls, tcp, anycpu, uwp
Last push: 2026-08-09T13:20:52+00:00

## Health v2 (maintenance only)
Score: 87/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 96, release rhythm 67, longevity 100
- inputs: {"age_days": 3457, "days_push": 24, "days_rel": 63, "gap_med": 131.0, "n_releases_24m": 5}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5062, forks 1154 (observed 2026-08-28T04:09:09.224065+00:00)

## What it is
MQTTnet is a high-performance .NET library implementing the MQTT protocol (up to version 5), providing both an MQTT client and an embedded MQTT server (broker). It supports TCP, TLS, and WebSocket channels with a uniform async API across .NET Framework, .NET Core, and UWP.

## Use cases
- connect IoT devices to an MQTT broker from .NET
- embed an MQTT broker in a .NET application
- publish and subscribe to MQTT topics with QoS support
- communicate with Azure IoT Hub over MQTT
- build a lightweight pub/sub messaging layer in C#

## When to choose
- you need MQTT client or broker functionality in any .NET application
- you want high message throughput with no external dependencies
- you need support for MQTT 3.1.1 and 5.0 in one API
- you want automatic connection and subscription management via ManagedMqttClient

## When to avoid
- you need a standalone production broker with clustering and persistence out of the box
- your project is not on a .NET platform
- you need an MQTT server on UWP with TLS, which is unsupported

## Facets
- artifact type: library
- maturity: active
- function: message-queue, networking, websocket, sdk
- domain: iot, microservices, developer-tools
- platform: dotnet, cross-platform, windows
- tags: mqtt, mqtt-client, mqtt-broker, iot-communication, tls, pubsub, csharp, messaging, linux, macos

## Member repositories
- dotnet/MQTTnet (main) score 87

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:09.224065+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:17:18.575799+00:00, confidence not recorded.
  - readme: https://github.com/dotnet/MQTTnet (fetched 2026-08-28T04:09:09.224065+00:00, sha 78b120b9c271)
- Data as of 2026-08-30T08:39:29.467469+00:00.