Prediction markets have exploded in popularity. Platforms like Polymarket and Kalshi now move millions of dollars every day as traders bet not on stocks, but on the world itself — elections, economic reports, policy decisions, sports outcomes, and everything in between.
Today, we’re bringing that world to developers with the Prediction Markets API, a new data feed built for anyone who wants programmatic access to event-based markets.
Instead of price data for companies, you now get price data for questions.
Will inflation rise next month?
Will Congress pass a bill?
Who wins the election?
Our API lets you track the probabilities the moment the crowd shifts.
What is the Prediction Markets API?
The Prediction Markets API is a REST API that gives you structured access to markets based on real-world events. It works just like financial market data — tickers, quotes, OHLCV, order books — but the underlying “asset” is a yes/no contract tied to an outcome.
You can pull data in JSON or MessagePack, and every endpoint follows a simple, resource-first structure.
Key Features
1. Market Listings
List every active or historical market on any supported exchange.
You get the market’s title, its resolution criteria, and its status — everything you need to index, classify, or build a discovery UI.
2. Real-Time Activity
Use /v1/activity/{exchange_id}/{market_id}/latest to track trades and quotes as they happen.
Perfect for alerting systems, dashboards, or bots that need immediate updates.
3. Historical OHLCV Data
Pull time-series data for any market outcome using:/v1/ohlcv/{exchange_id}/{market_id}/history
Supports:
- seconds
- minutes
- hours
- days
- years
This gives analysts the same tools they use for stocks — but applied to events.
4. Order Book Snapshots
Use /v1/orderbook/{exchange_id}/{market_id}/current to get bids, asks, and market depth.
Vital for liquidity analysis, spread modeling, and arbitrage screens.
Real Use Cases
1. Visualizing Political Probabilities
Pull daily OHLCV for a market like/v1/ohlcv/polymarket/pres_2024/history
Then plot how the “Who will win?” odds move with debates, scandals, and polls.
2. Monitoring Volatility Before Big Events
Use/v1/activity/{exchange}/{market}/latest
to watch volume spikes ahead of inflation reports, Fed decisions, or regulatory deadlines.
A sudden jump?
The crowd knows something.
3. Finding Arbitrage
Query the order book for all outcomes of the same event:/v1/orderbook/{exchange}/{market}/current
Compare “Yes” vs. “No” prices.
Look for gaps.
Execute.
Prediction markets create inefficiencies that traditional markets iron out — which makes them perfect for model-driven traders.
Start Building With Prediction Markets
Prediction Markets API lets you treat the future like a dataset.
Political odds. Economic expectations. Sports outcomes.
Policy decisions.
All structured. All programmatic. All ready to plug into your product.
Grab an API key. Hit your first endpoint.
Build something that sees the future a little earlier.
To get started, you can look at the full Prediction Markets API documentation.
