--- title: "One Time Password" description: "Authelia utilizes one time passwords as one of it's second factor authentication methods." lead: "Authelia utilizes one time passwords as one of it's second factor authentication methods." date: 2022-06-15T17:51:47+10:00 draft: false images: [] menu: overview: parent: "authentication" weight: 230 toc: true aliases: - /docs/features/2fa/one-time-password.html --- __Authelia__ supports time-based one-time password generated by apps like [Google Authenticator]. {{< figure src="2FA-TOTP.png" caption="An example of the time-based one time password authentication view" alt="Second Factor OTP Authentication View" width=300 >}} After having successfully completed the first factor, select __One-Time Password method__ option and click on __Register device__ 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. {{< figure src="REGISTER-TOTP.png" caption="An example of the time-based one time password registration view" alt="Second Factor OTP Registration View" width=400 >}} You can then use [Google Authenticator] or an authenticator of your choice to scan the code in order to register your device. {{< figure src="google-authenticator.png" caption="The Google Authenticator application" alt="Second Factor OTP Registration View" width=150 >}} 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__. This is standard practice, as a user can obviously register a second device with the same QR Code. As there is no tangible benefit and it is harder to keep track of multiple devices it's not a feature we will implement. [Google Authenticator]: https://google-authenticator.com/