> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/apis.md).

# Openfeed APIs

Welcome to the **Openfeed Technical Documentation**.

Openfeed is Barchart’s market data protocol and delivery platform, designed to provide fast, reliable access to global exchange data through a single integration.

Instead of building and maintaining multiple exchange connections, Openfeed allows you to **consolidate full-pipe market data into one API connection**. The platform delivers **low-latency data in its native exchange format**, helping teams reduce infrastructure complexity while lowering development and maintenance costs.

### Available APIs

Openfeed provides two APIs for accessing market data, depending on your application needs.

**There are two application programming interfaces (APIs) available when accessing Barchart's Openfeed platform:** 

**Streaming API** is designed for applications that monitor **large symbol universes** (for example, more than 2,000 instruments).

This API uses a real-time feed handler and is supported by SDKs in multiple languages:

* **Java**
* **.NET**
* **Go**
* **Python** (for data science and data operations)
* **TypeScript / JavaScript** (for front-end applications and visualizations)

The Streaming API is ideal for systems that require **continuous real-time market data across many instruments**.

#### REST API

The **REST API** provides access to Openfeed using a **query–response model**. It returns **JSON payloads**, allowing clients to request market data for specific instruments without implementing a streaming feed handler.

This API works best for applications that monitor a **smaller symbol universe** (typically fewer than 2,000 instruments).

Typical use cases include:

* Web applications
* Backend services
* Data pipelines
* Symbol-specific monitoring tools

### Jump right in

<table data-view="cards"><thead><tr><th></th><th></th><th></th><th data-hidden data-card-cover data-type="files"></th><th data-hidden></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h4><i class="fa-bolt">:bolt:</i></h4></td><td><strong>Quick Start</strong></td><td>Learn how to get started with Openfeed</td><td></td><td></td><td><a href="/pages/7FvWQMF0kTK7HGhlQfmo">/pages/7FvWQMF0kTK7HGhlQfmo</a></td></tr><tr><td><h4><i class="fa-lightbulb-gear">:lightbulb-gear:</i></h4></td><td><strong>Best Practices</strong></td><td>Optimize your app for stability and performance</td><td></td><td></td><td><a href="/pages/KTteUf0XRQ9kb6Wem4yR">/pages/KTteUf0XRQ9kb6Wem4yR</a></td></tr><tr><td><h4><i class="fa-globe-pointer">:globe-pointer:</i></h4></td><td><strong>SDKs</strong></td><td>Jump start your development process</td><td></td><td></td><td><a href="/pages/udkEPbjdJRzvL7xXvnso">/pages/udkEPbjdJRzvL7xXvnso</a></td></tr></tbody></table>


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