Massive (formerly Polygon.io)
Market data API for stocks, options, indices, currencies and futures.
Free plan, paid from $29/moHistorical and real-time market data
Stocks Basic $0 (5 calls/min, end-of-day); Stocks Starter $29/mo billed monthly. Checked 2026-10-14.
Quick start
Start on Stocks Basic to prototype, then upgrade only if you need real-time or more history.
Good and not so good
- Clean REST and WebSocket APIs
- Free tier for testing
- Real-time data on higher plans
Use cases with Massive (formerly Polygon.io)
No use cases yet. Add an agent use case.
Suggested in setups
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