Microproduct data guideintermediate

Polymarket Public Market Data

Continuously updated prediction-market questions, prices, liquidity, volume, trades, and order books for analyzing forecasts and event-driven markets.

Start the guide Open official source

At a glance

Difficulty
Intermediate — some data preparation helps
Size
Medium · ≤1 GB
Formats
JSON, API
Access
API
API key
Not required
Provider
Polymarket
Updates
Continuous
Data terms
Polymarket Terms of Use

From source to product signal

Test a product idea in four steps

Polymarket's public Gamma API exposes current market metadata without an API key. Start with a bounded page of active markets and save when the response was retrieved. Treat prices as changing market signals, not guaranteed or independently calibrated probabilities.

1

Check the setup

  • Python 3.10 or newer
  • A notebook environment such as Jupyter or Google Colab
  • An internet connection
2

Access the data

  1. 1.Read the official market-data overview and provider terms before using the API.
  2. 2.Request a bounded page of active markets from the public Gamma API.
  3. 3.Attach a retrieval timestamp to the response before comparing markets.
Open official source
3

Run the Python example

Install the packages, then run the notebook cell.

python -m pip install pandas requests

from datetime import datetime, timezone
import pandas as pd
import requests

url = "https://gamma-api.polymarket.com/markets"
response = requests.get(
    url,
    params={"active": "true", "closed": "false", "limit": 100},
    timeout=30,
)
response.raise_for_status()
markets = pd.json_normalize(response.json())
markets["retrieved_at"] = datetime.now(timezone.utc)
print(markets[["question", "volume", "liquidity"]].head())
4

Test a useful signal

Compare liquidity across active markets

Identify which active questions have the deepest markets and test whether liquidity and volume tell the same story.

  1. 01Convert volume and liquidity fields to numeric values and inspect missing data.
  2. 02Rank markets by liquidity and compare that ranking with trading volume.
  3. 03Explain why price, liquidity, trading volume, and forecast quality are different concepts.

Dataset details

Polymarket is a company source. Last verified 2026-08-10. Temporal coverage: current and historical markets.

Domains

Prediction MarketsFinanceCurrent Events

Data types

Event DataTime SeriesOrder Book

Tasks

Market MonitoringForecast EvaluationEvent Analysis

Geography

Global

Formats

JSONAPI

Provider

Polymarket

Data terms

Polymarket Terms of Use