Best Real-Time Streaming (WebSocket) Stock Data APIs (2026)
Every vendor we track with stock coverage and a documented streaming feed (WebSocket, or a raw streaming protocol for Databento), sorted by lowest listed paid plan. Streaming access often starts above the cheapest tier and many plans cap how many symbols you can stream at once, so check the WebSocket and real-time columns before you buy.
Comparison
| Asset classes | Real-time | WebSocket | Rate limits | ||||
|---|---|---|---|---|---|---|---|
| EODHDMarket data | Free tier | $19.99 | 30+ | global-stocks, etfs, forex, crypto, indices, commodities, fundamentals | Live/delayed (free: 15-min) | yes (Intraday & ALL-IN-ONE: 50 tickers; stocks US + Europe, forex and crypto global) | Free: 20/day, 20/min; paid: 100,000/day, 1,000/min |
| Massive (formerly Polygon)Market data | Free tier | $29 | 20+ | us-stocks, options, indices, forex, futures | real-time on Stocks Advanced; 15-min delayed on Starter/Developer | yes (Starter and up) | Free: 5 calls/min; paid: unlimited |
| Twelve DataMarket data | Free tier | $29 | unknown | stocks, etfs, forex, crypto, commodities, bonds, mutual-funds | Real-time US stocks (Grow+), real-time forex/crypto | yes (WS credits; trial on Basic/Grow) | API credits per minute: 8 (free) up to 10,946 |
| ThetaDataMarket data | unknown | $40 | 14+ | options, stocks, indices, interest-rates | real-time | streaming (Pro) | Concurrent-request limits: 2/4/8 |
| FinnhubMarket data | Free tier | $49.99 | 40+ | us-stocks, fundamentals, etfs, forex, crypto, bonds, economic | unknown | yes (Free 50 symbols; Basic 250; Standard/Pro unlimited) | Free 60 calls/min; All-In-One 900/min market data, 300/min fundamentals |
| AlpacaBroker + data | Free tier | $99 | 7+ | us-stocks, options, crypto | Free: IEX real-time websocket; Plus: all US exchanges | yes | Free: 200 calls/min; Algo Trader Plus: unlimited |
| IntrinioMarket data | unknown | $150 | 50+ | us-stocks, options, fundamentals, etfs | Real-time (EquitiesEdge/OptionsEdge) and 15-min delayed | yes (WebSocket on some feeds) | unknown |
| DatabentoMarket data | Free tier | Pay-as-you-go ($/GB); $125 free credits | 16+ | futures, options, us-stocks | live data on subscription plans | Raw TCP + client libraries (live streaming) | Unlimited downloads, streaming and API calls on subscriptions |
— means not stated on official pages. Not investment advice.
Official pricing pages
- EODHD ↗ Affiliate link
- Massive (formerly Polygon) ↗
- Twelve Data ↗
- ThetaData ↗
- Finnhub ↗
- Alpaca ↗
- Intrinio ↗
- Databento ↗
Some outbound links are affiliate links; that never changes the data. How we make money.