r/u_TanujLabs

One problem kept coming up while building IoT projects: backend development would stall because the hardware wasn't ready yet.

So I built a browser-based MQTT Explorer & Device Simulator that lets you develop and test MQTT workflows without waiting for ESP32s, sensors, or PLCs.

Current features:

• Connect to any MQTT broker (TCP/WebSocket)
• Publish and subscribe to topics in real time
• Explore your MQTT topic tree
• Simulate virtual devices
• Send custom JSON payloads
• Test backend APIs before hardware arrives
• Runs entirely in the browser (no installation)

Some use cases I've been using it for:

• Testing IoT dashboards
• Developing Home Assistant integrations
• Validating backend logic
• QA testing MQTT message flows
• Simulating smart home devices
• Industrial automation prototypes

The simulator can mimic things like:

• Temperature & humidity sensors
• GPS trackers
• Energy meters
• Custom devices with your own payloads

The project is still in its early stages, and I'm actively improving it.

Planned features include:

• Device template library
• Payload generator
• Saved broker profiles
• Webhook testing
• Team workspaces
• More protocol integrations

I'd really appreciate feedback from the community.

What features would make a tool like this genuinely useful in your workflow?

You can try it here:
https://mqtt.tanujlabs.com

Feedback, bug reports, and feature requests are all welcome. I'm building this based on real developer needs.