--- layout: default title: Time-based One-Time Password nav_order: 1 parent: Second Factor grand_parent: Features --- # Time-based One-Time Password **Authelia** supports Time-base one-time password generated by apps like [Google Authenticator].
After having successfully completed the first factor, select **One-Time Password method** option and click on **Not registered yet?** link. This will e-mail you to confirm your identity. *NOTE: If you're testing **Authelia**, this e-mail has likely been sent to the mailbox available at https://mail.example.com:8080/* Once this validation step is completed, a QR Code gets displayed.
You can then use [Google Authenticator] to scan the code in order to register your device. From now on, you get tokens generated every 30 seconds that you can use to validate the second factor in **Authelia**. ## Limitations Users currently can only enroll a single TOTP device in **Authelia**. Multiple single type device enrollment will be available when [this issue](https://github.com/authelia/authelia/issues/275) has been resolved. [Google Authenticator]: https://google-authenticator.com/