Prediction Markets: Kalshi, Polymarket & PredictIt Odds

Live odds from the four biggest prediction markets in one table: Kalshi, Polymarket, Manifold and PredictIt. Every market comes back with its probability, bid and ask, 24-hour change, volume, liquidity, open interest, close date and, once settled, the result. Search by keyword or category, paste market links, add daily price history, and schedule it to get an alert row whenever a market moves by the points you choose.

Built for traders and forecasters, journalists and newsletters, quant and research teams, app and bot builders, and AI agents.

What you get

One row per contract: a yes/no market, or one outcome of a multi-outcome event (each candidate in an election, each rate decision at a Fed meeting).

Field	Meaning
platform, marketId, eventId, eventTitle, question, outcome, url	The market
probability	Market-implied chance of "yes", 0 to 1 (midpoint of a tight book, else the last trade)
lastPrice, yesBid, yesAsk, noBid, noAsk, spread	Quotes, 0 to 1 (a $0.62 contract = 62%)
change24h, change7d	Probability change over 24 hours and 7 days (where shown)
volume, volume24h, volumeUnit, openInterest, liquidity, traders	Activity
outcomes	Every outcome with its price (Polymarket)
category, openTime, closeTime	When it trades
status (open, closed, resolved), result, resolutionStatus, rules	How it settles
priceHistory	[{date, probability, volume}], one point per day, with History days set (Kalshi, Polymarket)
previousProbability, movePoints	On alert runs: the price last delivered and the move since, in percentage points

{
  "platform": "kalshi",
  "eventTitle": "Fed decision in Dec 2026? (On Dec 9, 2026)",
  "question": "Will the Federal Reserve Hike rates by 0bps at their December 2026 meeting?",
  "outcome": "Fed maintains rate",
  "probability": 0.29,
  "yesBid": 0.28,
  "yesAsk": 0.3,
  "change24h": 0.01,
  "volume": 841358.21,
  "volume24h": 85959.14,
  "volumeUnit": "contracts",
  "openInterest": 462480.26,
  "closeTime": "2026-12-09T18:59:00Z",
  "status": "open",
  "url": "https://kalshi.com/markets/kxfeddecision"
}

Why this Actor

• Four platforms, one shape. Compare the same question across Kalshi, Polymarket, Manifold and PredictIt without four parsers.
• Search and categories. Keywords (fed rate, bitcoin, world cup) or 14 categories: politics, elections, economics, finance, crypto, sports, tech and science, AI, climate and weather, culture, world, companies, health, mentions.
• Paste links. Kalshi tickers or links, Polymarket event or market links, Manifold links, PredictIt links or ids.
• Move alerts. Set Alert on moves to e.g. 5 and schedule hourly: each run returns only markets whose probability moved 5+ points since you last got them, with the old and new price.
• Price history. Daily probability for up to a year per market, ready to chart.
• Settled markets too. Status closed returns resolved markets with the winning outcome.
• For AI agents. Callable as an MCP tool.

How to use it

Busiest markets on Kalshi and Polymarket right now:

{ "platforms": ["kalshi", "polymarket"], "maxItems": 50 }

Every Fed-rate market on all four platforms, with 30 days of history:

{ "platforms": ["kalshi", "polymarket", "manifold", "predictit"], "search": "fed rate", "historyDays": 30 }

Elections closing in the next 14 days, biggest movers first:

{ "categories": ["elections"], "closesWithinDays": 14, "sortBy": "move24h" }

Alert when any big crypto market moves 5 points (schedule hourly):

{ "platforms": ["kalshi", "polymarket"], "categories": ["crypto"], "minVolume24h": 10000, "alertMovePoints": 5 }

Specific markets by link:

{ "markets": ["https://polymarket.com/event/fed-decision-in-december-20260729232808632", "KXFEDDECISION-26DEC"] }

Options

Option	What it does
Platforms (platforms)	kalshi, polymarket, manifold, predictit (default Kalshi + Polymarket)
Search (search)	Keywords in the question, event or outcome, e.g. fed rate, bitcoin
Categories (categories)	politics, elections, economics, finance, crypto, sports, tech-science, ai, climate-weather, culture, world, companies, health, mentions
Markets (markets)	Links from any of the four sites, Kalshi tickers, Polymarket slugs or condition ids, PredictIt ids
Status (status)	open (default), closed (includes resolved, with result) or all
Sort by (sortBy)	volume24h, volume, liquidity, closingSoon, newest, move24h
Minimum total / 24-hour volume (minVolume, minVolume24h)	Each platform's own unit: contracts (Kalshi), US dollars (Polymarket), MANA (Manifold)
Minimum liquidity (minLiquidity)	In US dollars
Closes within (days) (closesWithinDays)	Only markets settling within this many days
History days (historyDays)	Daily price history, up to 365 days
Max markets (maxItems)	Most rows per run
Only new (onlyNew, monitorName)	With a schedule, each run returns only markets earlier runs did not deliver
Alert on moves (alertMovePoints)	Return only markets whose probability moved at least this many percentage points since last delivered

Pricing

$3 per 1,000 markets, plus a small start fee per run. Price history is included. On the Apify free plan a run returns up to 100 markets.

Good to know

• Volume units differ: Kalshi counts contracts, Polymarket US dollars, Manifold play money (MANA). volumeUnit says which; the volume filters apply in each platform's own unit.
• Manifold is play money; its probabilities are still a useful crowd forecast.
• PredictIt lists politics only and shows no volume, so it is left out when a volume or liquidity minimum is set.
• Sorting by volume or liquidity takes the top of each platform in turn, since units differ; closing soon, newest and biggest move sort across all.
• The first alert run returns every match as the baseline; later runs return only moves (and markets that are new to the search).
• Prices are delayed snapshots for research, not a trading feed.
• Questions: tacps126@gmail.com.