By the makers of zunoy
Connect to a free, always-on MQTT broker for learning, testing, and prototyping. No signup — use for basic testing and development.
Terms, limits, and reporting info for the free public MQTT broker — not intended for production use.
FreeMQTT is a public, free broker for learning, testing, and prototyping only — not for production, staging, or UAT.
All policies apply equally to our web presence on third-party platforms (e.g., GitHub, X, LinkedIn) as well as to our newsletter.
Expect flakiness: No SLA — servers may be updated or restarted, retained messages can be lost, and connections can drop. Implement reconnect/backoff logic and don’t rely on durability.
Play nice: No illegal activity, spam, crypto-mining, or attempts to overload the service. Keep message sizes small and avoid excessive simultaneous connections.
We can act: We reserve the right to disconnect or block abusive clients/IPs. The broker is provided “as-is” — no warranties or uptime guarantees; liability is limited to the extent permitted by law.
Report problems: For abuse or urgent issues email support@zunoy.com. For general issues contact support.
Explore practical ways to use FreeMQTT for testing, learning, and rapid prototyping — no setup, no friction.
Quickly test sensors, microcontrollers, and IoT devices without setting up your own infrastructure.
Learn MQTT fundamentals publish, subscribe, inspect messages and experiment with topic, QoS & retained flags.
Prototype real-time apps and dashboards using live data and validate functionality before moving to production.
Copy-paste connection examples for popular tech stacks. All examples use TLS/SSL ports for secure connections.
1const mqtt = require('mqtt');2const client = mqtt.connect('mqtts://mqtt.freemqtt.com:8883');34client.on('connect', () => {5 client.subscribe('test/topic');6 client.publish('test/topic', 'Hello from Node.js');7});
Follow these guidelines for reliable testing and to avoid common pitfalls when using our free broker.
Everything you need for seamless MQTT testing and development, available instantly.
No registration or setup required - start testing in seconds
Hosted on reliable cloud infrastructure with automatic restarts and periodic maintenance for stability.
Completely free to use for learning, research, and prototyping — no account or hidden limits.
Accessible worldwide — test from microcontrollers, web apps, or cloud systems without location restrictions.
Supports MQTT v3.1, v3.1.1, and v5 over TCP, WebSocket, and secure TLS/WSS connections.
Backed by robust infrastructure to ensure consistent uptime and minimal latency during peak usage.
Discover more developer utilities from Zunoy — open, free, and ready to use instantly. No sign-up, no payments, no personal details. Just tools that work.
Retrieve your iOS UDID instantly for development provisioning and device management.
Instant mock endpoints and sample JSON for frontend testing and prototyping.
FreeMQTT is one of our free developer tools. For production needs, see our paid SaaS platform with enterprise reliability and support.
© 2025 Mentcube Technologies Pvt. Ltd. • Part of the Zunoy Suite.
All rights reserved. All tools under the Zunoy Suite are owned, maintained, and operated by Mentcube Technologies Pvt. Ltd. v0.1.0
For legal information, including Terms of Service, Privacy Policy, and Acceptable Use Policy, visit zunoy.com/legal. By using this site, you agree to our use of cookies and similar technologies as described in our policies.
