Unusual Whales vs Polygon.io
Market data plus the curated alternative-data feeds Polygon does not ship: real-time options unusual activity, dark pool prints, congressional trades, and 13F flows.
The 30-second answer
Equities and options market data, OHLC, quotes, and option chains via REST and WebSocket.
Real-time options unusual activity feed, sweep / block / multi-leg classification, and dark pool prints on top of the raw market data.
Congressional trades, insider Form 4 transactions, 13F institutional flows, and an MCP integration for AI agents.
Feature comparison
Verified 2026-05-04. Comparison reflects publicly available information at the time of writing.
| Capability | Unusual Whales | Polygon.io |
|---|---|---|
| REST API for equities and options | ✓ Yes | ✓ Yes |
| WebSocket streaming | ✓ Yes | ✓ Yes |
| OHLC bars and historical price data | ✓ Yes | ✓ Yes |
| Option chains and contract data | ✓ Yes | ✓ Yes |
| Real-time options unusual activity feed | ✓ Yes | — |
| Sweep, block, and multi-leg classification | ✓ Yes | — |
| Dark pool print feed with NBBO context | ✓ Yes | — |
| Congressional trade tracking | ✓ Yes | — |
| Insider Form 4 transactions | ✓ Yes | — |
| 13F institutional flow tracking | ✓ Yes | — |
| Earnings calendar and analytics | ✓ Yes | — |
| Net premium and net flow analytics | ✓ Yes | — |
| Greek exposure (GEX/DEX/Vanna/Charm) feed | ✓ Yes | — |
| Kafka streaming (enterprise) | ✓ Yes | — |
| MCP integration for AI agents | ✓ Yes | — |
Why people switch from Polygon.io to Unusual Whales
Curated, not just raw
Polygon ships raw market data. Unusual Whales ships the analyzed feeds on top: unusual options activity, sweeps, blocks, multi-leg, dark pool prints, GEX, net premium, all production-ready.
Alternative data included
Congressional trades, insider transactions, and 13F flows are part of the same API, not separate vendors to integrate.
AI-native
Plug Unusual Whales into Claude, ChatGPT, or Cursor through MCP and ask natural-language questions across raw market data and curated alt-data in a single integration.
Built-in dashboard
If you also want a UI, Unusual Whales ships one out of the box with the same data the API serves.
Frequently asked
Is Unusual Whales a Polygon.io replacement?+
If you use Polygon for options and equities market data, yes. Unusual Whales also provides options chains, OHLC, and historical bars, plus the curated unusual-activity, dark pool, congressional, and institutional feeds Polygon does not include.
Can I get raw OPRA-tape options data on Unusual Whales?+
Yes. Full options trades and quotes are available through the WebSocket and Kafka streaming feeds on the appropriate plan tiers.
Does Unusual Whales have an API for backtesting?+
Yes. Historical options flow, OHLC, GEX exposure, and curated event feeds are all available via REST with date-range filters.
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