> ## 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.
# Fillout (API Key) - How do I link my account?
# Overview
To authenticate with Fillout (API Key), you need:
1. **Hostname** - Your Fillout instance URL
2. **API Key** - A key that grants Nango permission to interact with Fillout's API resources and services
This guide will walk you through finding both your **Hostname** and **API Key** within Fillout.
## Prerequisites
* You must have a Fillout account
## Step 1: Finding your hostname and API key
1. Navigate to [Developer settings](https://build.fillout.com/home/settings/developer).
2. Click **Enable API** if you haven't already done so.
3. Your **Hostname** will appear in the **Base URL** field. It is the value between `https://` and `/v1/api`. In the example below, the **Hostname** is `api.fillout.com`. Your **API Key** will be shown in the **API Key** field.
## Step 2: Enter credentials in the Connect UI
Once you have both your **Hostname** and **API Key**:
1. Open the form where you need to authenticate with Fillout (API Key).
2. Enter your **Hostname** and **API Key** in their respective fields.
3. Submit the form to complete authentication.
You are now connected to Fillout (API Key).