> ## 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.

# Builder.io (Private) - How do I link my account?

# Overview

To authenticate with Builder.io (Private), you will need:

1. **API Key** – A private key that grants Nango permission to use Builder.io's Write API.
2. **Domain** – The API domain (e.g. `builder.io`) of the API you want to connect to.

This guide walks you through finding or creating your **Private API Key** and **Domain** in Builder.io.

### Prerequisites

* You must have a registered account with Builder.io.

### Instructions

#### Step 1: Finding your API domain

Different APIs within Builder.io use different domains. The **Write API** uses `builder.io`. For more details and the correct domain for each API, see the [API Intro](https://www.builder.io/c/docs/api-intro).

#### Step 2: Finding your API key

1. **Log in** to your [Builder.io](https://builder.io) dashboard.
2. Select your space and go to **Space settings** in the sidebar.
3. Under **Space Settings**, find **Private Keys** and click **Edit**.

<img src="https://mintcdn.com/nango/R6BB1CoVCLOn79sv/api-integrations/builder-io-private/builder_io_api_key.png?fit=max&auto=format&n=R6BB1CoVCLOn79sv&q=85&s=37948dd917b3a0d7594625da5db69516" width="3024" height="1480" data-path="api-integrations/builder-io-private/builder_io_api_key.png" />

4. In the modal, view your existing private API key or create a new one if needed.

<img src="https://mintcdn.com/nango/R6BB1CoVCLOn79sv/api-integrations/builder-io-private/generate_api_key.png?fit=max&auto=format&n=R6BB1CoVCLOn79sv&q=85&s=a4807193fedd3b26fcf623e29a810fe2" width="1608" height="1230" data-path="api-integrations/builder-io-private/generate_api_key.png" />

#### Step 3: Enter credentials in the Connect UI

Once you have the **API Key** and **Domain**:

1. Open the form where you need to authenticate with Builder.io (Private).
2. Enter the **API Key** and **Domain** in the designated fields.
3. Submit the form to complete authentication.

<img src="https://mintcdn.com/nango/R6BB1CoVCLOn79sv/api-integrations/builder-io-private/form.png?fit=max&auto=format&n=R6BB1CoVCLOn79sv&q=85&s=2bf126dbcfeb03cf0fdc667efcca1517" style={{maxWidth: "450px" }} width="498" height="699" data-path="api-integrations/builder-io-private/form.png" />

You are now connected to Builder.io (Private).