Yes/No) and a price per outcome in 0..1. An event groups related markets — for example a presidential election event holds one market per candidate.
Markets
List markets
Paginate and filter by
active, eventId, source; sort by volume, liquidity, or end date.Trending markets
Top markets by 24h volume.
Get a market
Full market detail by
slug.Current prices
Best bid/ask, midpoint, and spread per outcome.
Order book
Full CLOB depth for both outcomes, best-first, live from the venue.
Price history
Yes-price time series over
1h…max intervals.OHLC candles
OHLC bars for the Yes outcome at your chosen interval/fidelity.
Price at time
The last Yes price at or before a given timestamp (no interpolation).
Cross-venue match
The matching market on the other venue (Kalshi ↔ Polymarket), with a confidence score and price delta.
Events
List events
Filter by
active, closed, source; sort by volume or end date.Trending events
Top events by 24h volume.
Get an event
Event detail including its child markets.
Cross-venue matches
Every child market’s counterpart on the other venue (Kalshi ↔ Polymarket) in one call.
Venues: list and trending endpoints accept
source=polymarket or source=kalshi; omit it to get both venues mixed. Every item carries its own source field.Cross-venue match: use the cross-venue endpoints to compare the same question across both books. The response returns the counterpart market(s), a
confidence score (0..1), and delta (current Yes minus the matched venue’s Yes) — the basis for spotting arbitrage/pricing gaps. match is null (with a reason) when the market is not in a curated group or no confident counterpart exists.