> For the complete documentation index, see [llms.txt](https://docs.plock.io/plock-overview/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.plock.io/plock-overview/use-cases/for-developers/api/authentication.md).

# Authentication

## Using the API key

Your API key must be present in each request made towards this API. They key should be sent using the `Authorization` header following the `Bearer` prefix. For example:

```
curl -H "Authorization: Bearer <API KEY>" https://endpoint.plock.io/c1/api
```