Guides / Comparison

ProbSights vs. Polygon.io

Polygon.io is a stocks/options/forex/crypto market data API oriented around traditional finance. It's not built around prediction market structure — no yes/no or up/down orderbooks, no resolution outcomes, no cross-venue event matching. ProbSights is built specifically for Kalshi and Polymarket.

	ProbSights	Polygon.io
Prediction market coverage	Kalshi + Polymarket	No
Yes/No, Up/Down orderbook data	Yes	No
Cross-venue arbitrage scanner	Yes	No
Whale trade tracking	Yes	No

Related

• ProbSights vs. PolyHistorical
• Best prediction market data provider

Related guides

• Best Prediction Market Arbitrage Tool: Evaluation Guide
• Best Prediction Market Data Provider: What to Look For
• Best Prediction Market Whale Tracker: Evaluation Guide
• Free Kalshi Historical Data: What's Actually Free

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