Instant messaging service for students and employees of the University

heiCHAT is Heidelberg University's instant messaging service which facilitates internal University communication via

  • Chat (with individuals or in groups with any number of participants)
  • Audio calls (one-on-one)
  • Video calls (one-on-one)

The Computing Centre operates its own server for heiCHAT, which can be reached via the provided link "heiCHAT web interface".

You can access this server using a browser or with the recommended Element client, which is available for all major operating systems.

Target group

  • Students
  • University employees
  • Doctoral candidates
  • Instructors


  • Data-protection-compliant and encrypted communication in real time via chat and audio/video calls
  • Use with your Uni ID via browser or the recommended Element client


  • Facilitation of communication and collaboration in working groups, for example
  • No need to share personal data (e.g. your telephone number) to communicate with fellow students
  • Keep your private and study-related communication separate

University employees

  • Chat and videotelephony for uncomplicated communication with colleagues
  • Beneficial use in digital teaching:
    • Student working groups
    • Q&A chats between instructors and students
    • Interaction elements

Access and requirements

Using heiCHAT via browser

heiCHAT can be used directly on your browser. Click on the provided link “heiCHAT web interface” and log in with your Uni ID – registration is not required.

Using heiCHAT via desktop or mobile client

If you would like to use heiCHAT via an app, we recommend the open-source client Element. Element is available for a variety of operating systems – simply follow the provided link to access the download.

After you have installed Element on your device, you need to enter the address of the heiCHAT server to use it:

On Windows/MacOS/Linux

  1. Start Element.
  2. Go to the Sign In screen, and under “Homeserver” next to “matrix.org.” click on “Edit.”
  3. In the pop-up window, click on the text field "Other homeserver".
  4. Enter the following address in this text field: 


  5. Click “Continue” and then sign in with your Uni ID (e.g. xy123).

On Android/iOS

  1. Start the Element app.
  2. Click on "Get started“.
  3. Select "Other – Custom & advanced settings“.
  4. Select the text field “Address” and enter: 


  5. Then select “Continue”
  6. Select “Sign In” and enter your Uni ID (e.g. xy123) and the corresponding password. Then select "Sign In".

You can find more information in the illustrated how-to linked below.

Using heiCHAT with an alternative desktop or mobile client.

Since heiCHAT is based on the open-source Matrix protocol, you can, in principle, use any client that supports this protocol. A complete list of compatible clients can be found on the Matrix website.

Please note: heiCHAT has only been tested with the recommended Element client. Therefore, you may encounter errors or functional restrictions when using other clients.

Technical information

  • The URZ-operated server for heiCHAT uses the open-source Matrix communication protocol.
  • All data will be stored exclusively in the Computing Centre. There is no connection to the global Matrix server network ("Federation").
  • The service is designed in compliance with data protection regulations.
  • Connections are transport encrypted. End-to-end encryption can also be enabled in rooms and direct chats.

Frequently Asked Questions

Table filters


Are my messages encrypted?
Communication via the Matrix instance is transport encrypted. You also have the option of activating end-to-end encryption in rooms and direct chats.
Where are my messages saved?

This Matrix instance is a server operated by the University Computing Centre This means the data will be saved in the Heidelberg University Computing Centre.

Can I contact other members of the global Matrix network?

No, we are not part of the global federated Matrix network ("Federation"). You can only communicate with authorized members of Heidelberg University.

I successfully logged in. Why can't I chat with anyone or create rooms?

To use this service, you have to agree to the Terms of Service and the processing of your personal data.

When you first log in, the server administrator “@administrator:matrix-im.uni-heidelberg.de” will invite you to the room "Server Notices". After accepting the invitation and clicking on the provided link, you will be brought to a site with the Terms of Service and the Data Protection Policy. Please read them carefully, and to confirm your understanding and agreement, please click on “Einverstanden” (Agree).

Why can't I create a public room?

In order to ensure that conversations remain secure and are only read by those who should read them, only closed rooms are allowed on the University's Matrix server. Private rooms cannot be found through the search function, so you can invite users and determine who enters the rooms.