Custom flows

A custom flow refers to a user flow created entirely from scratch using the Clerk API. If prebuilt components don't meet your specific needs or if you require more control over the logic, you can rebuild the existing Clerk flows using the Clerk API.

How authentication flows work in Clerk

Before building custom authentication flows, read the following sections to get a general understanding of how authentication flows work in Clerk.

Sign-up flow

The SignUp object is the pivotal concept in the sign-up process. It is used to gather the user's information, verify their email address or phone number, add OAuth accounts, and finally, convert them into a User.

Every SignUp must meet specific requirements before being converted into a User. These requirements are defined by the instance settings you selected in the Clerk Dashboard⁠. For example, on the User & authentication⁠ page, you can configure email and password, email links, or SMS OTP as authentication strategies.

Once all requirements are met, the SignUp will turn into a new User, and an active session for that User will be created on the current Client.

Don't worry about collecting all the required fields at once and passing them to a single request. The API is designed to accommodate progressive multi-step sign-up forms.

The following steps outline the sign-up process:

1. Initiate the sign-up process by collecting the user's authentication information and passing the appropriate parameters to the create() method.
2. Prepare the verification.
3. Attempt to complete the verification.
4. If the verification is successful, set the newly created session as the active session by passing the SignIn.createdSessionId to the setActive() method on the Clerk object.
5. Check for any pending tasks that need to be completed by accessing Session.currentTask. Refer to session tasks

The state of a SignUp

The SignUp object will show the state of the current sign-up in the status property.

If you need further help on where things are and what you need to do next, you can also consult the required_fields, optional_fields, and missingFields properties.

Verified fields

Some properties of the SignUp, such as emailAddress and phoneNumber, must be verified before they are fully added to the SignUp object.

The SignUp object will show the state of verification in the following properties:

Sign-in flow

The SignIn object is the pivotal concept in the sign-in process.

Sign-ins are initiated by creating a SignIn object on the current Client. If the sign-in is successfully authenticated, it will transform into an active session for that User on the current Client.

The following steps outline the sign-in process:

1. Initiate the sign-in process by collecting the user's authentication information and passing the appropriate parameters to the create() method.
2. Prepare the first factor verification. Users must complete a first factor verification to prove their identity. This can be something like providing a password, an email link, a one-time code (OTP), a Web3 wallet address, or providing proof of their identity through an external social account (SSO/OAuth).
3. Attempt to complete the first factor verification.
4. Optionally, if you have enabled multi-factor for your application, you will need to prepare the second factor verification for users who have set up 2FA for their account.
5. Attempt to complete the second factor verification.
6. If verification is successful, set the newly created session as the active session by passing the SignIn.createdSessionId to the setActive() method on the Clerk object.
7. Check for any pending tasks that need to be completed by accessing Session.currentTask. Refer to session tasks

Session tasks

Session tasks require users to complete specific actions after authentication, such as selecting an organization. These tasks ensure that users meet all requirements before gaining full access to your application.

For detailed information about configuring and implementing session tasks, see the session tasks overview.

Steps to handle session tasks

After completing the sign-up or sign-in process, you should check if the user has any pending tasks:

1. Check for pending tasks: Use the navigate parameter in setActive() to access session.currentTask and check for pending session tasks.
2. Handle the task: If a task exists, build UI to guide the user through completing the required action based on the task type. See the available task types to understand what actions may be required.
3. Complete the flow: Once all required tasks are completed, the session becomes fully active and the user can access protected content.

You can build your own UI to handle specific task types. For example, if the task is choose-organization, you can create a custom organization creation component to allow users to create or select an organization before proceeding.

'use client'

import { RedirectToTasks } from '@clerk/nextjs'

export default function Page() {
  return <RedirectToTasks />
}

Next steps

Now that you have a general understanding of how authentication flows work in Clerk, you can start building your custom flows. To get started, choose the guide that best fits your needs from the navigation on the left.