Skip to main content
The ProbSights API provides programmatic access to prediction market data across Kalshi and Polymarket — including whale trades, cross-venue arbitrage, price spreads, and full-text search. All API routes are versioned under /v1/… on:

​
Quick start

Get a key from the dashboard, then use the Try playground on any endpoint page to send live requests.

​
What you can build

Market search

Full-text search across series, events, and markets with filters for exchange, category, volume, and status.

Arbitrage scanner

Find cross-venue arbitrage opportunities and price spreads between Kalshi and Polymarket.

Whale tracking

Monitor large trades across prediction markets. Track events and inspect whale feed and stats.

Webhooks

Push whale trades and arbitrage opportunities to your own HTTP endpoint instead of polling.

Historical data

Orderbook snapshots for Kalshi and Polymarket markets.