---
title: "MQTT Rules & Alerts | ConnectMQ"
description: "Threshold rules on MQTT payload fields with message templates, an alert log with the payload that triggered each alert, and browser notifications."
url: "https://connectmq.com/rules-alerts/"
language: "en"
---

Rules & alerts

# Turn MQTT data into alerts you can act on

Set thresholds on any payload field, get notified the moment one is crossed, and keep an audit log of every alert with the exact message that caused it.

[Try it free](https://app.connectmq.com/signup) [See pricing](https://connectmq.com/pricing/)

No card required

Rules

## Turn thresholds into alerts

Create rules on any topic with conditions on payload fields — for example {temp} > 70 — and a message template that fills in live values.

-   Conditions on JSON payload fields
-   Message templates with placeholders such as {temp}
-   Enable, edit and delete rules per topic

![ConnectMQ alert rules with a topic, a condition and an alert message template](https://connectmq.com/screens/rules.png)

Alerts

## Never miss a threshold violation

Every triggered rule lands in an audit log with the topic, device, time and the full payload that caused it — plus browser notifications as it happens.

-   Unread, read and archived alert views
-   The exact payload that triggered each alert
-   Desktop notifications from the browser

![ConnectMQ triggered alerts log with unread alerts and their payloads](https://connectmq.com/screens/alerts.png)

## Rules & alerts FAQ

What can a rule check?

A rule watches a topic and evaluates a condition on a field of its JSON payload — for example {temp} > 70. When the condition is met, an alert is created.

How am I notified?

Triggered alerts appear in the alert log and as desktop notifications from your browser.

Can I see why an alert fired?

Yes. Every alert stores the topic, device, time and the full payload that triggered it.

Platform

## More in every ConnectMQ workspace

[

### Dashboard & monitoring

Live topic cards, signals and ISA-95 workspace

Learn more](https://connectmq.com/monitoring/)[

### Digital Twin

Your factory in 3D with live MQTT telemetry

Learn more](https://connectmq.com/digital-twin/)[

### Connectivity

MQTT 3.1.1 and 5 over TCP, TLS, WS and WSS

Learn more](https://connectmq.com/connectivity/)

## Your private MQTT broker is a few clicks away

Create an account, get your broker credentials and connect your first device — no servers to install, patch or scale.

[Get started](https://app.connectmq.com/signup) [See pricing](https://connectmq.com/pricing/)

## Articles

[All articles](https://connectmq.com/blog/)

Industrial IoT

### [Sparkplug B and the Unified Namespace: Structuring Industrial IoT Data on MQTT](https://connectmq.com/blog/mqtt-sparkplug-b-unified-namespace/)

Sparkplug B gives industrial MQTT a strict session and payload model, while a Unified Namespace gives your plant data a single, readable home. Here is how they fit together, with topic design tips and live examples.

August 26, 20269 min read

MQTT Fundamentals

### [MQTT 5 Features That Matter in Practice: Reason Codes, Shared Subscriptions, Expiry and More](https://connectmq.com/blog/mqtt-5-features/)

MQTT 5 is more than a version bump. Learn the features that change how you build IoT systems, from reason codes and expiry to shared subscriptions and request/response, with hands-on examples.

September 22, 20269 min read

IoT Tutorials

### [ESP32 MQTT Tutorial: Publish Sensor Data and Control an LED with Arduino IDE](https://connectmq.com/blog/esp32-mqtt-tutorial/)

Connect an ESP32 to an MQTT broker with Arduino IDE and PubSubClient, publish JSON temperature readings, control the onboard LED from the command line and upgrade to TLS with portal credentials.

August 23, 20269 min read