Implement Passwordless SMS in Regular Web Apps
With an SMS connection, the user is asked to enter a phone number, to which Auth0 sends a one-time code using Twilio. The user then enters the code into your application.
If the phone number attached to the code matches an existing user, Auth0 authenticates the user:
If the user is new, their user profile is created for the
sms connection before they are authenticated by Auth0.
Open an account with Twilio
Configure the connection
- Enter your Twilio Account SID and Twilio Auth Token.
- Select your SMS Source and depending on your selection, enter either your Twilio Messaging Service SID or a From phone number. Users will see what you enter as the sender of the SMS.
- In Message, enter the body text of the SMS.
- Adjust settings for your OTP Expiry and OTP Length, and click SAVE.
The Message area supports multiple languages.
To choose the language, call the /passwordless/start authentication endpoint and set the value of the 'x-request-language' header. When this header is not set, the language is extracted from the 'accept-language' header, which is automatically set by the browser.
The Message area accepts Liquid syntax. You can use this syntax, combined with exposed parameter values, to programmatically construct elements of the message. For example, you can reference the
request_language parameter to change the language of the message:
The following parameters are available when defining the message template:
||The password to use|
||The user's phone number|
||The name of the application with which the user is signing up|
||The requested language for message content|
Enable your apps
Click the Apps tab, and enable the apps for which you would like to use Passwordless SMS.
Configure Callback URL
For security purposes, you must add the callback URL to the list of Allowed callback URLs in your application's Settings section of the Dashboard.
Lock with Passwordless Mode is a professional-looking dialog that allows users to log in after receiving a one-time password via email or text message.
Then you can trigger the login widget with the following code:
This will open a dialog that asks the user for their phone number.
Then Auth0 will use Twilio to send an SMS to the user containing the one-time code:
Lock will ask for the code that has been sent to the provided number via SMS. The code can then be used as a one-time password to log in:
Once the user enters the code received via SMS, Lock will authenticate the user and redirect to the specified
Use your own UI
Download a sample project specific to this tutorial configured with your Auth0 API Keys.
Construct a new instance of the Auth0 client as follows:
You must provide a way for the user to enter a phone number to which the SMS will be sent. Then you can begin the passwordless authentication as follows (assuming the name of your form input as
This will send an SMS to the provided phone number. The user must now enter the code they received into your custom UI. Then you can continue with the login as follows (assuming the name of your form inputs as
If authentication is successful, the user will be redirected to the
redirectUri specified in the Auth0 constructor.
Check out the Auth0.js SDK reference documentation for more information.