# Introduction

What you can build with the Estactics API and how it works.

The Estactics API lets your own systems work with your CRM data: send new leads from your website, keep properties in sync, or pull your pipeline into a report.

## How the API works

- Every request goes to `http://localhost:4000/api`.
- Requests are authenticated with an API key.
- Requests and responses use JSON.
- Your key can only reach data that belongs to your organization.

## Your first request

Once you have an [API key](/docs/api-keys), this request returns five of your clients:

```bash
curl --request POST \
  --url http://localhost:4000/api/clients/search \
  --header 'Authorization: Bearer YOUR_API_KEY' \
  --header 'Content-Type: application/json' \
  --data '{"fields": ["id", "fullName"], "limit": 5}'
```

## Where to go next

- [Create an API key](/docs/api-keys)
- [Try the API in your browser](/docs/try-the-api)
- [Browse the API reference](/reference)