# intro

- **URL:** https://marketplace.gohighlevel.com/docs/intro
- **Summary:** Welcome to the API documentation.

[Skip to main content](https://marketplace.gohighlevel.com/docs/intro#__docusaurus_skipToContent_fallback)

Version: v3

On this page

Welcome to the API documentation. This developer portal is your reference for integrating with our platform programmatically — automating workflows, syncing data, and building custom applications on top of the REST API.

What you can do[​](https://marketplace.gohighlevel.com/docs/intro#what-you-can-do "Direct link to What you can do")

The API gives you secure, programmatic access to core platform resources, including:

*   **Contacts** — create, update, search, and manage records.
*   **Conversations & Messaging** — send and receive messages across channels.
*   **Calendars & Appointments** — manage availability and bookings.
*   **Payments** — handle orders, transactions, and subscriptions.
*   **Webhooks** — subscribe to real-time events and react to changes as they happen.

How it works[​](https://marketplace.gohighlevel.com/docs/intro#how-it-works "Direct link to How it works")

The API is organized around standard REST conventions:

*   Predictable, resource-oriented URLs.
*   JSON-encoded request and response bodies.
*   Standard HTTP response codes to indicate success or failure.
*   OAuth 2.0 for secure, scoped authorization.

Authentication[​](https://marketplace.gohighlevel.com/docs/intro#authentication "Direct link to Authentication")

All requests are authenticated using **OAuth 2.0**. You'll exchange your credentials for an access token, then include that token in the `Authorization` header of each request:

    Authorization: Bearer YOUR_ACCESS_TOKEN

Access tokens are scoped, so an application only receives the permissions it has been granted.

Getting started[​](https://marketplace.gohighlevel.com/docs/intro#getting-started "Direct link to Getting started")

1.  **Create an app** to obtain your client credentials.
2.  **Authorize** and exchange your credentials for an access token.
3.  **Make your first request** to a resource endpoint.
4.  **Subscribe to webhooks** to receive real-time updates.

Use the navigation sidebar to explore the full API reference. Each endpoint includes request parameters, example payloads, and live code samples in multiple languages.

*   [What you can do](https://marketplace.gohighlevel.com/docs/intro#what-you-can-do)
    
*   [How it works](https://marketplace.gohighlevel.com/docs/intro#how-it-works)
    
*   [Authentication](https://marketplace.gohighlevel.com/docs/intro#authentication)
    
*   [Getting started](https://marketplace.gohighlevel.com/docs/intro#getting-started)