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

# API authentication

> How to send API keys to the FelixFusion public API.

To use the public API, you can send an API key in one of two ways. The backend accepts both formats on public `/v1` routes.

<a href="https://app.felixfusion.ai/settings/api" className="button primary">Get API key</a>

## Option 1: Add it to the header

```bash theme={null}
curl -H "x-api-key: YOUR_API_KEY" https://api.felixfusion.ai/v1/datasets
```

## Option 2: Use the `api_key` query parameter

```bash theme={null}
curl "https://api.felixfusion.ai/v1/datasets?api_key=YOUR_API_KEY"
```

Replace `YOUR_API_KEY` with your actual API key.