# ThetaData Streaming WebSocket API

**Canonical:** https://apis.io/apis/thetadata/thetadata-streaming-websocket-api/  
**Provider:** ThetaData — https://apis.io/providers/thetadata/  
**Base URL:** ws://127.0.0.1:25520/v1/events  
**Documentation:** https://docs.thetadata.us/Streaming/Getting-Started.html

ThetaData Streaming WebSocket API is one of 7 APIs that [ThetaData](https://apis.io/providers/thetadata/) publishes on the [APIs.io](https://apis.io/) network, described by an AsyncAPI event-driven specification. Tagged areas include Streaming, WebSocket, Trades, Quotes, and Real-Time. The published artifact set on APIs.io includes API documentation and an AsyncAPI specification.

JSON WebSocket streaming of US stock trade/quote, options trade/quote, and index price streams, served locally by the Theta Terminal at ws://127.0.0.1:25520/v1/events. Requires a paid subscription with streaming permissions; a single connection per user is permitted, with CONNECTED/DISCONNECTED status headers and QUOTE/TRADE/STATUS message types.

## Machine-readable artifacts (3)

- **Documentation** — https://docs.thetadata.us/Streaming/Getting-Started.html
- **AsyncAPI** — https://raw.githubusercontent.com/api-evangelist/thetadata/refs/heads/main/asyncapi/thetadata-streaming-asyncapi.yml
- **APIsJSON** — https://raw.githubusercontent.com/api-evangelist/thetadata/refs/heads/main/apis.yml

## Other ThetaData APIs (6)

- [ThetaData MCP Server](https://apis.io/apis/thetadata/thetadata-mcp-server/)
- [ThetaData Calendar API](https://apis.io/apis/thetadata/thetadata-calendar-api/)
- [ThetaData Index API](https://apis.io/apis/thetadata/thetadata-index-api/)
- [ThetaData Interest Rate API](https://apis.io/apis/thetadata/thetadata-interest-rate-api/)
- [ThetaData Option API](https://apis.io/apis/thetadata/thetadata-option-api/)
- [ThetaData Stock API](https://apis.io/apis/thetadata/thetadata-stock-api/)

## Tags

Streaming, WebSocket, Trades, Quotes, Real-Time

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/thetadata/thetadata-streaming-websocket-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/thetadata/.