## Overview

Using the `affirm.checkout.open()` function, you can direct your customers to Affirm's secure payment portal. This guide outlines the steps for executing this feature.

## Implementation Steps

### Using JavaScript for Initialization

Initiate the checkout process by creating your checkout object with `affirm.checkout()`. To transition the customer to the Affirm Checkout portal, call `affirm.checkout.open()`.

### Example

Here's a code example to guide you through the process:

## Parameters and Callbacks

### Method Arguments

### Callback Mechanisms

It's important to note that this method typically doesn't return a value. You should set redirection URLs using the checkout object. If your metadata setting isn't set to 'modal,' you'll need to implement the following callback functions:

• **onFail**: Called when the customer exits, cancels or is declined in the Affirm checkout flow.

• **onSuccess**: Triggered upon successful confirmation of the Affirm loan. This function yields a success object, which contains a `checkout_id`. Note that this `checkout_id` will be the value used to authorize the loan in the following Authorization request.

• **onOpen**: Called when Affirm Checkout is successfully initialized on the user interface.

• **onValidationError**: Alerts you in case of a validation error during the checkout request.