Use a custom certificate

By default, Zulip generates a signed certificate during the server install process. In some cases, a server administrator may choose not to use that feature, in which case your Zulip server may be using a self-signed certificate. This is most common for Zulip servers not connected to the public internet.


Most browsers will show a warning if you try to connect to a Zulip server with a self-signed certificate.

If you are absolutely, 100% sure that the Zulip server you are connecting to is supposed to have a self-signed certificate, click through the warnings and follow the instructions on-screen.

If you are less than 100% sure, contact your server administrator. Accepting a malicious self-signed certificate would give a stranger full access to your Zulip account, including your username and password.


Version 5.4.0 and above

Zulip Desktop version 5.4.0 and above use the operating system's certificate store, like your web browser.

  1. Hit Cmd + Space to bring up Spotlight Search, type Keychain Access, and press Enter.

  2. From the File menu, choose Import Items...

  3. Navigate to the certificate file, then click Open.

  4. Right-click the newly-added certificate, and click Get Info from the context menu.

  5. Expand the Trust section.

  6. Select Always Trust for the Secure Sockets Layer (SSL) option.

  7. Close the window. You will be prompted for your password to verify the change.

  8. Restart the Zulip Desktop application.

On Windows, Zulip Desktop shares the certificate store with Google Chrome, so you can add certificates to it from inside Chrome.

  1. Open Google Chrome.

  2. From the Chrome menu (⋮) in the top-right, select Settings.

  3. In the Privacy and Security section, click Security.

  4. Scroll down to and click Manage Certificates.

  5. Select the Trusted Root Certification Authorities tab.

  6. Select Import...

  7. Navigate to the certificate file, then click Open.

  8. Select Done.

  9. Restart the Zulip Desktop application.

The required packages and steps vary by distribution; see the Chromium documentation for detailed documentation. On most systems, once the nss tools are installed, the command to trust the certificate is:

certutil -d sql:$HOME/.pki/nssdb -A -t "P,," -n zulip \
  -i path/to/certificate.pem

You will need to restart the Zulip Desktop application to pick up the new certificate.

Version 5.3.0 and below

On Zulip Desktop version 5.3.0 and below, we require you to manually enter the certificate details before you can connect to your Zulip server. You'll need to get a certificate file (should end in .crt or .pem) from your server administrator and add it:

  1. Click the gear () icon in the bottom left corner of the app.

  2. Select the Organizations tab.

  3. Under Add Custom Certificates, enter your organization URL and add the custom certificate file (it should end in .crt or .pem).