Using the Polymarket Data API: Real-Time Prediction Market Data for Developers | Polymarket Alternative UK

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 empirical study. PolyGram provides access to Polymarket's comprehensive API infrastructure, enabling seamless integration with the globe's most liquid prediction market ecosystem.

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 across prediction markets in real time for targeted events
News tools: Identify and highlight markets responding to emerging developments
Aggregators: Benchmark Polymarket odds against competing platforms such as Kalshi and Metaculus
Alert systems: Trigger notifications whenever market movement exceeds predefined parameters
Academic research: Leverage historical settlement information to evaluate forecast quality and model performance

FAQ

Is the Polymarket API free to use?: Yes — market data via the Gamma API carries no cost subject to standard rate restrictions (approximately 100 requests per minute without authentication). Submitting orders on the CLOB requires wallet funding; however, all data retrieval operations remain complimentary.
Is there a Python library for Polymarket?: Multiple community-developed Python packages are available on GitHub. Look for "polymarket-py" to identify the most actively maintained implementations.