Free, open-source MQTT explorer and monitor for builders and testers.
I use MQTT brokers every day for apps and controls. Existing tools never quite delivered easy navigation, multi-broker handling, data simulation, highlighting and searching content, or flexible windowing — moving panels around and keeping multiple topic trees in view. TopicBench’s features grew from those daily needs.
I'm happy with the performance: among the MQTT desktop tools I've tried, TopicBench stays ahead on CPU, memory, and small download size — a native Rust app that keeps large topic trees responsive without a heavy footprint.
- Simultaneous multi-broker — connect to several brokers at once and monitor or search their topics in a single window
- Multi-broker profiles — save hosts, TLS/WSS options, and credentials (passwords in the OS keyring)
- Live topic tree — subscribe with wildcards and browse traffic as it arrives; keep multiple trees in view
- Flexible windowing — move panels and arrange the layout for how you work
- Search & highlight — find topics and payloads without leaving the desktop UI
- Publish & recent — send messages quickly and keep recent payloads handy
- Payload inspect — clear views for JSON and plain text
- Stickies & graphs — pin important topics and watch values over time
- Free & open source — use it, report issues, contribute
- Updates via GitHub Releases — in-app check for every install; bare Linux/Windows binaries can self-replace, packaged installs notify and may need a manual upgrade
- 100% Rust — built entirely in Rust for efficient memory and CPU use on large topic trees and lists
- Connection profiles (MQTT TCP / WebSocket, optional TLS)
- Concurrent live sessions across brokers in one window
- Topic subscriptions with
+/# - Shared sticky board across profiles
- Publish with QoS and retain
- Full keyboard shortcuts & navigation — F1 /
?help, panel toggles, search focus, and more
Latest free release: v1.2.5 — typical asset sizes below (from that release).
| Typical size | ||
|---|---|---|
| Windows portable (x64) | TopicBench-windows-x64-portable.zip | ~16 MB |
| Windows exe (x64) | topicbench-windows-x64.exe | ~32 MB |
| Linux binary (x64) | topicbench-linux-x64 | ~28 MB |
| Linux AppImage (x64) | TopicBench-x86_64.AppImage | |
| Debian / Ubuntu (.deb) | topicbench_1.2.5_amd64.deb | ~15 MB |
| Fedora / RHEL / openSUSE (.rpm) | topicbench-1.2.5-1.x86_64.rpm | |
| Arch / Omarchy (AUR) | topicbench-bin — yay -S topicbench-bin |
same as Linux binary |
| SHA-256 checksums | SHA256SUMS |
Windows: unzip the portable zip and run TopicBench.exe, or use the standalone .exe.
Linux binaries target glibc 2.35+ (Ubuntu 22.04 / Debian 12 and newer).
Updates: the bare Linux binary and Windows portable / bare .exe can apply updates in place (download → verify SHA-256 → replace their own files). AppImage, .deb, .rpm, and AUR installs still get in-app update notifications; installing the new package is usually manual (system paths aren’t writable by the app). Packaging scripts: packaging/README.md.
Arch: AUR package installs the Release binary + desktop entry (OSS only). PKGBUILD lives in-tree; publish steps in packaging/aur/README.md.
All releases · Source on GitHub
Paid extras for teams that outgrow the free explorer — same app, unlock Pro when you need them. Standalone download for licensed customers; the free app stays unrestricted for base features. Product page: TopicBench Pro.
- MCP server — connect, subscribe, publish, and wait from Cursor / CI against live sessions
- Topic & payload simulation — generators and formulas for whole payloads or JSON fields
- Record → simulate — capture live traffic, then suggest Simulate rows from the tape
- Scenario player — sequenced, timed multi-topic publish scripts
- Combined multi-topic graph — shared time axis across Graph stickies
- History scrubber — scrub per-topic history in the Payload panel
- Topic bookmarks — jump list into deep trees
- Custom color rules — paint tree rows by topic / payload predicates
- UI themes — pick a look that’s easier on the eyes or fits your environment
- Topic tree export & import — JSON hierarchy out, republish onto a target broker
- CSV recording — time-series dumps for Excel
Combined graphs let you overlay multiple channels on a single time-logged graph — useful for correlating data across topics and even across brokers.
Simulation publishes scripted MQTT data into your live sessions. You can also auto-create simulations from recorded sessions to replicate datasets with a best-guess prediction of the observed series.
Color rules highlight topics in the tree based on payload matches, topic matches, and individual values within payloads.
Bookmarks jump you anywhere in a tree and auto-expand that topic for immediate access.
Requirements: Rust stable ≥ 1.80 (rustup update stable), plus Linux GUI libs (typically libxcb, libxkbcommon, and a Vulkan/GL stack).
git clone https://github.com/unipsycho/topicbench.git
cd topicbench
cargo run --releaseProfiles: ~/.config/topicbench/profiles.json
Settings: ~/.config/topicbench/settings.json
Windows: native cargo build --release on Windows works; the Windows icon is embedded via winres (MinGW windres when cross-compiling from Linux).
MIT OR Apache-2.0. See LICENSE-MIT and LICENSE-APACHE.