Masqott icon

Masqott

Visualizing MQTT data the macOS way

Why Masqott

MQTT brokers are chatty, hierarchical, and hard to inspect. Command-line clients show you a firehose; most GUIs show you a flat list. Masqott instead mirrors the broker's structure as a live outline you can expand, search, publish into, and open in multiple windows — the way a native Mac app should feel.

MasqottScreenshot

Features

Browse the whole tree, live

  • Outline view of the entire topic hierarchy, updating in real time as messages arrive.
  • Multi-window — open the whole server in one window and a single subtopic in another, side by side. Open any subtopic in its own new window.
  • Keyboard navigation — use arrow keys to navigate, expand/collapse whole hierarchies with ⌥ + left/right arrow.
  • Pause updates to study a moment without the tree shifting underneath you.
  • context menu to show/hide table columns (with helpful column tooltips).

Connect securely

  • Username / password authentication.
  • Broker metadata display, so you can see what the server reports about itself.
  • TLS and mutual TLS (mTLS) support (disabled to avoid export restrictions, will be available in later App Store builds).

Publish with ease

  • Double-click or context-menu publish straight from a topic.
  • A dedicated publish window with a large topic field, value editor, and JSON formatting/syntax highlighting.
  • Publish history to recall and resend earlier messages.
  • Clear visual feedback the moment a message is sent.
  • Honest retained-message handling, with tooltips explaining the retain flag.

Find what matters

  • Find across the tree, with filterable search results.
  • Prev/next navigation that starts from your current selection.

Represented Devices

Some groups of subtopics really describe one physical thing — its name, IP, online state, firmware version. Masqott can recognize such groups and create a single readable summary line on the parent topic, instead of making you drill into every subtopic.

  • Ships with built-in device definitions (ESP32/ESP-IDF, Home Assistant discovery, OpenMQTTGateway, and more).
  • Fully user-extensible via a JSON file — match topics structurally, pull values from payloads or JSON, and render them with inline color and SF Symbol markup. Your definitions merge with and override the built-ins.

Organize your workflow

  • Favorites and Open Recent for the brokers and topics you return to.

  • URL support — open a broker, navigate to a topic, and even publish, all from a link:

    open mqtt://mqtt.local:1883/home/test?value=123&retain=false&publish=true

Requirements

  • macOS
  • An MQTT broker (with optional TLS / mTLS / credentials)

Get Started

  1. Download Masqott and unpack it if needed.
  2. Move Masqott to your Applications folder
  3. Launch it!
  4. Press ⌘N to connect to your MQTT server — and start browsing.