> ## Documentation Index
> Fetch the complete documentation index at: https://nango.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# How to register your own Square Sandbox OAuth app

> Register your own OAuth app and configure Square Sandbox for use in Nango

This guide will show you how to register your application with Square (Sandbox) to obtain your own OAuth credentials (client id & secret) for development and testing.

Once you complete this guide, your users can grant your app access to their Square Sandbox account. You will have full access to the Square Sandbox API for testing.

<Steps>
  <Step title="Sign in to the Developer Console and create an application">
    1. Sign in to the Square Developer Console and navigate to the [apps](https://developer.squareup.com/apps) section.
    2. Click the **+** button to create a new application.
    3. Enter a name for your application, then submit.
    4. Select the products you wish to integrate with and the audience for the application.
    5. Click **Complete** to finish registering your application.
  </Step>

  <Step title="Switch to Sandbox and get your credentials">
    1. At the top of the page, toggle the **Sandbox** button so you are in Sandbox mode. This ensures you retrieve sandbox client credentials (not production).
    2. In the **Sandbox.Redirect URL** section, update your **Redirect URL**: `https://api.nango.dev/oauth/callback`.
    3. Copy your **Sandbox.Application ID** (Client ID) and **Sandbox.Application Secret** (Client Secret). You will need these when configuring your integration in Nango.
  </Step>

  <Step title="Next">
    Follow the [*Quickstart*](/getting-started/quickstart).
  </Step>
</Steps>

For more on the Square OAuth flow, see the [Square OAuth API reference](https://developer.squareup.com/reference/square/o-auth-api).

## Testing in Sandbox

Square requires you to **launch the seller test account** from the Developer Dashboard before you can initiate the OAuth flow.

1. In the [Square Developer Console](https://developer.squareup.com/apps), navigate to [Sandbox test accounts](https://developer.squareup.com/console/en/sandbox-test-accounts).
2. Select a test account, or create one if you don't have one.
3. In the modal that appears, click **Open in Square Dashboard**.
4. Once the Sandbox Dashboard is open in the same browser tab, you can initiate the OAuth flow in Nango. Authorize the connection from that tab so the Sandbox session is active.