lowskillcoding/pdata-prediction-markets

pdata.world prediction markets

Prices, volumes and results for prediction markets on eight venues — Polymarket, Kalshi, Manifold, Myriad, Limitless, Predict, Opinion and Gemini — in one schema. The data is collected by pdata.world, which polls each venue every 10 to 60 minutes, and is published under CC BY 4.0.

This snapshot was taken on 2026-10-07. It has three parts:

Config	Rows	What one row is
resolved (default)	450,216 events, with their top 1,752,957 markets (at most 10 each)	An event pdata stopped tracking after it closed, with each top market's reported result
markets-open	417,132	A market open for trading: price, 24h move and volume
events-open	38,356	An open event, which groups the markets of one question

from datasets import load_dataset

resolved = load_dataset("lowskillcoding/pdata-prediction-markets", "resolved", split="train")
markets = load_dataset("lowskillcoding/pdata-prediction-markets", "markets-open", split="train")

# or with pandas
import pandas as pd
df = pd.read_parquet("hf://datasets/lowskillcoding/pdata-prediction-markets/data/markets-open.parquet")

Rows per venue

• resolved: kalshi 194,286, gemini 118,368, polymarket 115,407, predict 15,216, limitless 6,438, opinion 344, manifold 148, myriad 9
• markets-open: polymarket 268,382, kalshi 112,611, gemini 11,900, manifold 10,848, predict 10,667, limitless 1,435, opinion 1,255, myriad 34
• events-open: polymarket 18,596, kalshi 13,751, predict 2,211, manifold 1,672, gemini 1,273, limitless 547, opinion 272, myriad 34

Read this before using the numbers

• probability and prices are on a 0–1 scale.
• Volume is not comparable across venues. volume and volume_24hr are in each venue's own unit: shares for Polymarket and contracts for Kalshi (each pays $1 at resolution), play-money mana for Manifold, and each other venue's figure as it reports it. pdata's report How eight venues count volume explains each one.
• In resolved, a market's probability is the last price pdata saw, which is usually after the market settled. It records the result; it is not a forecast. For prices before close, use the API's history endpoint while a market is live (history is deleted 10 days after close) — see How accurate were prediction-market prices a day before the result? for one way to do it.
• result is null where the venue never reports one. Of the 1,752,957 archived markets, 1,006,292 carry a result.
• A gap in resolved: events that closed between 2026-06-02 and 2026-08-11 are missing, because they were pruned before a backup was taken. Events closed in the 10 days before the snapshot are in neither file yet.
• pdata groups Kalshi's sibling events for one game under a single group event (is_group), whose volume is the sum of its children's.

Fields

resolved

Every event pdata has stopped tracking live, with its final result: the record pdata keeps when it prunes an event, 10 days after it closes. Events closed more recently are in neither file yet. Kept since 2026-08-31; events pruned before then were rebuilt on 2026-10-07 from backups taken 2026-05-09 to 2026-08-29. Events that closed between 2026-06-02 and 2026-08-11 are missing: they were pruned before the next backup was taken.

Field	Meaning
source	Venue: polymarket, kalshi, manifold, myriad, limitless, predict, opinion or gemini.
id	The venue's event id, unique within source.
title	Event title when pdata pruned it.
categories	pdata topic categories (e.g. Politics, Sports), from rules and AI tagging.
closed_time	When the event closed (UTC): the venue's close time, else its end date, else when pdata last saw it.
markets	The event's top markets by lifetime volume, at most 10: id, question, result (as the venue reported it; null where the venue never says), final probability (0-1) and lifetime volume (venue unit).
url	The event or market's own page on the venue's website; null when it cannot be built.
pdata_url	pdata's page for the event, https://pdata.world/events/{source}/{id}.
pruned_at	When pdata wrote this record (UTC): when it pruned the event, or 2026-10-07 for an event pruned before 2026-08-31 and rebuilt from backups.

markets-open

Every market open for trading on the 8 venues pdata tracks, one per line: price, 24h move and volume. A market is one yes/no question, or one outcome of a multi-outcome event.

Field	Meaning
source	Venue: polymarket, kalshi, manifold, myriad, limitless, predict, opinion or gemini.
id	The venue's market id, unique within source.
event_id	The parent event's id (same source); joins events-open on (source, id).
event_title	The parent event's title. Read question with it: an outcome of a multi-outcome event can be a bare label.
question	The market's question as the venue titles it.
label	Short outcome label where the venue gives one (e.g. a candidate's name).
categories	pdata topic categories (e.g. Politics, Sports), from rules and AI tagging.
outcomes	Outcome labels in venue order, usually ["Yes", "No"].
outcome_prices	Price of each outcome, 0-1, in outcomes order.
probability	Implied probability of the first outcome (usually YES), 0-1.
prob_24h_change	Change in probability over the trailing 24h, on the same 0-1 scale (0.05 = up 5 points). Null when there is no snapshot in that window.
volume	Lifetime trading volume. Venue-reported, in the venue's own unit and not converted across venues: shares for Polymarket and contracts for Kalshi (each pays $1 at resolution), play-money mana for Manifold, and each other venue's figure as it reports it.
volume_24hr	Trading volume over the last 24 hours. Venue-reported, in the venue's own unit and not converted across venues: shares for Polymarket and contracts for Kalshi (each pays $1 at resolution), play-money mana for Manifold, and each other venue's figure as it reports it.
liquidity	Liquidity as the venue reports it, in the venue's own unit.
open_interest	Open interest as the venue reports it, in the venue's own unit.
start_date	When the market opened, as the venue reports it (UTC).
end_date	Scheduled close or expiry, as the venue reports it (UTC).
status	The venue's own status string, verbatim; null for Polymarket.
countries	Countries the market concerns (full English names, at most 3), from pdata's AI tagging. [] means none applies; null means not tagged yet.
updated_at	When pdata last wrote this row (UTC): every fetch from the venue, and again when pdata recomputes a derived field.
url	The event or market's own page on the venue's website; null when it cannot be built.
pdata_url	pdata's page for the event, https://pdata.world/events/{source}/{id}.

events-open

Every event open for trading on the 8 venues pdata tracks, one per line. An event groups the markets of one question; markets-open holds its markets.

Field	Meaning
source	Venue: polymarket, kalshi, manifold, myriad, limitless, predict, opinion or gemini.
id	The venue's event id, unique within source (pdata builds the id of a group event).
title	Event title as the venue publishes it.
categories	pdata topic categories (e.g. Politics, Sports), from rules and AI tagging.
start_date	When the event opened, as the venue reports it (UTC).
end_date	Scheduled close or expiry, as the venue reports it (UTC).
volume	Lifetime trading volume. Venue-reported, in the venue's own unit and not converted across venues: shares for Polymarket and contracts for Kalshi (each pays $1 at resolution), play-money mana for Manifold, and each other venue's figure as it reports it.
volume_24hr	Trading volume over the last 24 hours. Venue-reported, in the venue's own unit and not converted across venues: shares for Polymarket and contracts for Kalshi (each pays $1 at resolution), play-money mana for Manifold, and each other venue's figure as it reports it.
open_interest	Open interest as the venue reports it, in the venue's own unit.
mutually_exclusive	True when exactly one of the event's markets can resolve YES; false when they are independent questions; null when the venue does not say.
market_count	How many markets the event has (for a group event, across its child events).
is_group	True for an event pdata built to group sibling Kalshi events of one matchup.
parent_event_id	The pdata group event this event belongs to, or null.
synthetic	True for an event pdata created to wrap a market the venue lists without one.
updated_at	When pdata last wrote this row (UTC): every fetch from the venue, and again when pdata recomputes a derived field.
url	The event or market's own page on the venue's website; null when it cannot be built.
pdata_url	pdata's page for the event, https://pdata.world/events/{source}/{id}.

Timestamps are UTC. The manifest each file was built from is in manifests/.

Updates and versions

A new snapshot is added monthly; each is tagged with its date (this one is 2026-10-07), so load_dataset("lowskillcoding/pdata-prediction-markets", "resolved", revision="2026-10-07") always returns the same rows. For daily data, the same three files are rebuilt every night at https://api.pdata.world/bulk/ as gzipped JSON lines.

Other ways to get the data

• REST API, no key: https://api.pdata.world/docs
• MCP server for AI assistants: https://api.pdata.world/mcp
• Read-only Postgres with price history: postgresql://pdata_readonly:pdata_public_2026@pg.pdata.world:6433/pdata_new (the password is published on purpose)
• Python client and examples: https://github.com/noskillcoding/pdata-client
• Research built on this data: https://pdata.world/research

Licence and citation

CC BY 4.0. Credit "Data: pdata.world" with a link to https://pdata.world. This snapshot is archived on Zenodo with DOI 10.5281/zenodo.23211611. The underlying market data remains subject to each venue's own terms. pdata.world is independent and not affiliated with any venue.

@misc{pdata_world_prediction_markets_2026_10_07,
  title        = {pdata.world prediction markets: prices, volumes and results from eight venues},
  author       = {{pdata.world}},
  year         = {2026},
  note         = {Snapshot 2026-10-07},
  doi          = {10.5281/zenodo.23211611},
  howpublished = {\url{https://huggingface.co/datasets/lowskillcoding/pdata-prediction-markets}}
}