> For the complete documentation index, see [llms.txt](https://docs.thingsup.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thingsup.io/mqtt/test-mqtt-connection.md).

# Test MQTT Connection

### MQTT Client

Now user can use MQTT Client option to establish a MQTT connection and to perform pubsub operations. Go to **Experiment** section from left menu of dashboard and choose **MQTT Client**. 

Here user need to enter same **Client ID**, **Username** and **Password** used while adding a device.

{% hint style="info" %}
Username will be the Device Key starting with your account ID.The Client ID and Password will be the same you have entered during [**Add Device**](/mqtt/add-mqtt-device.md) process. 
{% endhint %}

![MQTT Test Client](/files/FBlb7Qcqm1KydVsy1gNJ)

#### Subscribe to topic

User can subscribe to a topic which he has mentioned while adding device to account.

{% hint style="info" %}
User has to make sure he has chosen *sub* or *pubsub* option to given topic.
{% endhint %}

![Subscribe to MQTT Topic](/files/R0TKAejZezpLEwXmmOUA)

#### Publish to topic

User can publish to a topic which he has mentioned while adding device to account.

{% hint style="info" %}
User has to make sure he has given *pub* or *pubsub* option to given topic.
{% endhint %}

![Publish to MQTT Topic](/files/iXXJQjv08vxYVxLxSB9Q)

User can see the list of *Message already sent* and *Messages Received* in side section.