Using the Polymarket Data API: Real-Time Prediction Market Data for Developers | Polymarket Qué Es

In this guide

Available Data Endpoints
Python Quickstart
Use Cases
FAQ

Developers, researchers, and analysts increasingly rely on prediction market intelligence for strategic decision-making and quantitative work. The Polymarket platform—integrated through PolyGram—furnishes comprehensive APIs that grant access to the globe's most extensive prediction market dataset, enabling builders to construct sophisticated applications atop this foundation.

Available Data Endpoints

Gamma API (Market Data)

GET https://gamma-api.polymarket.com/events
  ?limit=100&active=true&order=volume24hr
  Returns: event metadata, current prices, volume, tags

GET https://gamma-api.polymarket.com/events/{slug}
  Returns: full event with all markets, prices, descriptions

GET https://gamma-api.polymarket.com/markets/{conditionId}
  Returns: single market details, current order book price

CLOB API (Order Book)

GET https://clob.polymarket.com/book
  ?token_id={tokenId}
  Returns: full order book depth (bids/asks)

GET https://clob.polymarket.com/prices/history
  ?market={conditionId}&resolution=1h&startTs=1700000000
  Returns: hourly price history

WebSocket: wss://ws-subscriptions-clob.polymarket.com
  Subscribe to real-time price updates

Python Quickstart

import requests

# Get top prediction markets by volume
r = requests.get(
    "https://gamma-api.polymarket.com/events",
    params={"limit": 10, "active": "true", "order": "volume24hr"}
)
for event in r.json():
    market = event["markets"][0] if event.get("markets") else {}
    prices = market.get("outcomePrices", "[0.5,0.5]")
    import json; p = json.loads(prices)
    print(f"{event['title'][:50]}: YES={float(p[0]):.2%}")

Use Cases

Research dashboards: Monitor probability shifts within prediction markets across defined time intervals and particular outcomes
News tools: Identify and highlight markets experiencing significant movement in response to current events
Aggregators: Benchmark probability estimates between Polymarket, Kalshi, and Metaculus platforms
Alert systems: Trigger notifications whenever market movements exceed predetermined tolerance bands
Academic research: Leverage resolved market data to evaluate prediction accuracy and forecaster performance metrics

FAQ

Is the Polymarket API free to use?: Absolutely—data retrieval via the Gamma API incurs no cost, though unauthenticated requests face rate restrictions (roughly 100 calls per minute). Submitting orders through the CLOB requires a wallet with sufficient funds, yet querying market data remains complimentary.
Is there a Python library for Polymarket?: Multiple community-developed Python packages are available on GitHub. Look for "polymarket-py" to find actively maintained implementations.