MQTT

aid: mqtt
name: MQTT
description: 'MQTT (Message Queuing Telemetry Transport) is an OASIS-standard, lightweight publish/subscribe messaging transport
  protocol designed for constrained devices and low-bandwidth, high-latency, or unreliable networks, making it the de-facto
  messaging protocol for IoT and machine-to-machine (M2M) communication. MQTT is a protocol specification rather than a hosted
  API: clients connect over TCP/TLS (typically port 1883 or 8883) or WebSocket (8080/8081) to an MQTT broker (such as Mosquitto,
  HiveMQ, EMQX, or AWS IoT Core) and exchange CONNECT, PUBLISH, SUBSCRIBE, and other control packets defined by the standard.
  The current standard is MQTT Version 5.0 (OASIS Standard, 7 March 2019); MQTT 3.1.1 remains widely deployed.'
type: Index
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
- MQTT
- Messaging
- Publish Subscribe
- IoT
- M2M
- Protocol
- OASIS Standard
- Telemetry
url: https://raw.githubusercontent.com/api-evangelist/mqtt/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-05-30'
specificationVersion: '0.19'
apis:
- aid: mqtt:protocol-v5
  name: MQTT Version 5.0 Protocol
  description: OASIS Standard publish/subscribe messaging protocol for IoT and M2M communication. MQTT v5.0 defines the wire
    format and behavior of CONNECT, PUBLISH, SUBSCRIBE, UNSUBSCRIBE, PINGREQ, DISCONNECT and other control packets exchanged
    between MQTT clients and brokers over TCP (typically 1883, or 8883 with TLS) or WebSockets. Authentication is broker-specific
    and may include username/password, X.509 client certificates, or OAuth/JWT enhanced authentication.
  humanURL: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html
  baseURL: mqtt://broker.example.com:1883
  tags:
  - MQTT 5.0
  - Protocol
  - Publish Subscribe
  - OASIS
  - IoT
  properties:
  - type: Specification
    url: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html
  - type: Specification PDF
    url: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.pdf
  - type: OASIS Standard Page
    url: https://www.oasis-open.org/standard/mqtt-v5-0-os/
  - type: Specifications Index
    url: https://mqtt.org/mqtt-specification/
  - type: AsyncAPI
    url: https://raw.githubusercontent.com/api-evangelist/mqtt/refs/heads/main/asyncapi.yml
- aid: mqtt:protocol-v3-1-1
  name: MQTT Version 3.1.1 Protocol
  description: Previous OASIS Standard version of MQTT, still widely deployed across IoT brokers, devices, and cloud platforms.
    MQTT 3.1.1 defines the publish/subscribe messaging semantics, QoS levels 0/1/2, retained messages, and last-will-and-testament
    that are inherited and extended by MQTT 5.0.
  humanURL: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html
  baseURL: mqtt://broker.example.com:1883
  tags:
  - MQTT 3.1.1
  - Protocol
  - Publish Subscribe
  - OASIS
  - IoT
  properties:
  - type: Specification
    url: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html
  - type: Specification PDF
    url: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.pdf
common:
- type: GitHubOrganization
  url: https://github.com/mqtt
- type: Website
  url: https://mqtt.org
- type: Specification
  url: https://mqtt.org/mqtt-specification/
- type: OASIS Technical Committee
  url: https://www.oasis-open.org/committees/tc_home.php?wg_abbrev=mqtt
- type: Software Listings
  url: https://mqtt.org/software/
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com