Prediction Markets Scraper: Polymarket + Kalshi Odds API

Get live odds, implied probabilities, prices, volume and liquidity from Polymarket and Kalshi in one clean, unified dataset. No API keys, no login, no coding.

Use it to track elections, crypto price markets, Fed decisions, sports, AI and tech events, and compare what both markets think about the same question.

What you get

One row per market, with the same fields for both platforms:

Field	Example
platform	polymarket / kalshi
title	Will the price of Bitcoin be above $90,000 on October 7?
impliedProbabilityPct	93.7
yesPrice / noPrice	0.937 / 0.063
bestBid / bestAsk / lastPrice	0.93 / 0.94 / 0.937
priceChange1d / priceChange1w	0.04
volume24h / volumeTotal / volumeUnit	122896 / 2.1M / USD
liquidityUsd / openInterest	52160
category, eventTitle, status, startDate, endDate, description, url, scrapedAt

Why this scraper

• Two platforms, one schema. No more stitching two different APIs together.
• Smart filters. Keywords, category, minimum 24h volume and liquidity, so you only pay for markets you care about.
• Skips dead and expired markets by default.
• Uses the official public APIs. Fast, reliable, no browser, no blocking.
• Pay only for results. $2 per 1,000 markets, no monthly rental.

How to use

1. Pick platforms (Polymarket, Kalshi or both).
2. Add keywords like bitcoin, election, fed, nfl, openai, or leave empty for everything.
3. Optionally set Minimum 24h volume to remove inactive markets.
4. Set Max results and click Start.
5. Download as JSON, CSV, Excel, or pull via the Apify API. Schedule it hourly to build your own odds history.

Example input

{
  "platforms": ["polymarket", "kalshi"],
  "keywords": ["bitcoin", "ethereum"],
  "minVolume24h": 1000,
  "maxItems": 200
}

Use cases

• Traders & quants: cross-platform price comparison and arbitrage screening.
• Journalists & analysts: what the markets think about elections and news.
• Dashboards & bots: feed Google Sheets, Slack alerts, or your own app via API.
• Researchers: build historical odds datasets by scheduling runs.

Notes

• Kalshi volume is reported in contracts (each pays $1 if correct); Polymarket volume is in USD. See volumeUnit.
• Data comes from the platforms' official public APIs. This Actor is not affiliated with Polymarket or Kalshi. Not financial advice.

Feedback

Missing a field or a platform (Manifold, PredictIt, Limitless)? Open an issue on the Actor page and it will be added.