Signup form with phone OTP verification with Auth0 template

Verify your users' phone number sending them a one-time-password (OTP) and sign them up with Auth0.

Signup form with phone OTP verification with Auth0

About this template

This signup form with Auth0 includes:

  1. A initial step that requires the phone number.
  2. A flow that generates an OTP and sends it via SMS.
  3. A third step that requires the verification code.
  4. And last, a flow that verifies the OTP, updates the Auth0 user profile and resumes the authentication flow.

How to configure this template


1. An Auth0 account.

2. Creating a Machine-to-Machine Auth0 application to use the Management API with Arengu. Learn here how to create one.

3. Adding Arengu Progressive Profiling action to Auth0 with the following settings:

  • Arengu Form URL
  • Required user fields
  • Login count for profiling
  • Arengu session token
This template uses a test-only action to send SMS. Consider replacing it by your own SMS provider (eg. Twilio) before using it in production to avoid limitations.

Arengu Form URL

The URL where you will embed your form. For testing purposes you can use the preview page (eg. https://preview.arengu.page/YOUR_FORM_ID)

Required user fields

We will add "prompted_phone_verification". This boolean will determine if user has already passed the verification.

In this template, Arengu will store "phone_number" and "phone_verified" inside the "user_metadata" Auth0 property. Depending on your connection (eg. SMS connection), consider changing this inside the flow action:

Login count for profiling

We will set this value to 1, as we want this step as required to all users that sign up and before allowing them to access.

Arengu session token

Add a long random string that we will use to communicate between Arengu and Auth0 in a secure way:

After adding the secret to Auth0, make sure you add it to the "Verify JSON web token" and "Sign JSON web token" actions in Arengu:

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Explore the docs

Need some inspiration?

Discover our best practices guides to design the perfect signup flow, examples of other SaaS companies, and success stories of our clients.

Integrate this template with your own stack

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Getting started with Arengu

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