Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesFor prediction-market data, start with each platform’s documented API rather than scraping its page markup. Identify the event and market, retain the platform’s distinct identifiers, then collect the specific observations you need—such as prices, order books, trades, or historical points. The details differ by venue, so build separate collectors and normalize their outputs only after preserving each source’s original fields.
Decide what you need to collect
“Prediction market data” can mean several different things. Choose the observation before writing a collector: it determines the route, identifiers, time parameters, and interpretation required.
- Market metadata: event and market definitions, outcomes, and identifiers.
- Current prices: the price for a particular outcome.
- Order books: available bids and asks at a point in time.
- Historical prices: price observations over a requested interval.
- Trades or activity: executed or reported activity, where the platform exposes it.
- Account data: orders, trades, or portfolio information tied to a user; this is a different access boundary from public market data.
Polymarket’s market-data overview describes read and streaming use, while its separate trading quickstart covers CLOB authentication and order placement. Do not add trading credentials or order logic to a public-data collector unless the project actually needs account or trading functions.
Understand Polymarket’s event-to-outcome model
Polymarket documents the hierarchy as event → market → outcome. An event can group one or more markets; a market is a tradable question with YES and NO outcomes, and each outcome has its own token ID. For price and order-book collection, the outcome token ID is the identifier to use.
#1 Best Overall
- FARMERS MARKET TILE LAYING STRATEGY GAME: In the Market Fresh game, go up against fellow farmers to run the most successful stand! Stack a stall with produce and shut competitors out of the market
- BEAUTIFUL TACTILE TILES: Draft colorful tiles shaped like crates of fruit and veggies. Strategically place them on a shopfront board to earn points. The more produce players stack, the more they’ll earn
- EASY TO LEARN, CHALLENGING TO MASTER: This immersive spatial puzzle game is easy enough for players of all skill levels to quickly learn, while the strategy brings them to the table again and again
- AWARD-WINNING DESIGNERS: By Azul creator Michael Kiesling and Wolfgang Kramer, the renowned team behind many bestselling strategy board games
- SOLO PLAY & EXTRA CHALLENGES: Enjoy as a 1 player game to master the market! For more challenges, flip the boards for smaller grids, or try a variation that rewards more points for higher stacks
Keep the IDs in separate fields. Event IDs, Gamma market IDs, on-chain condition IDs, and CLOB token IDs refer to different entities or systems; treating them as one generic id makes joins and later debugging unreliable.
| Field to retain | What it identifies or represents | Why keep it |
|---|---|---|
event_id |
The event grouping one or more markets | Preserves the event-to-market relationship. |
market_id |
The market record (including the Gamma market identifier where supplied) | Identifies the question independently of its outcomes. |
condition_id |
The on-chain condition, when supplied | Retains the platform’s distinct on-chain reference. |
outcome_label |
The named outcome, such as YES or NO | Makes an observation interpretable without relying on array position. |
token_id |
The outcome token | Used to request that outcome’s price or order book. |
Preserve the original response alongside any normalized record if auditability matters. The exact fields vary by route; do not assume every response contains every identifier.
Plan pagination and historical collection
Follow the endpoint’s cursor
Polymarket Data API v2 feed routes use opaque cursors. Follow each returned next_cursor until it is null, and keep the filters unchanged during a paginated walk where the route requires that. The reference warns that changing filters while paging some feeds can silently re-anchor a walk. A collector that mutates its filters midway can therefore miss records without producing an obvious error.
Rank #2
- NOW STEM.org Certified!!! Now being played in over 22+ countries and every state in the USA!!!!
- No Stock Knowledge needed to have a Great Time!!!!! Based on real stock market principles.
- 3 Levels of Play - Family Friendly, Strategy level, and Teams Play
- No financial, economics, or heavy math required. A fun way to learn about finance and money management.
- Ages 10+ to adult / 2-6 Players
Some walks are sensitive to concurrent updates: offset-style pages can skip or repeat rows as data refreshes. Record collection timestamps and cursor checkpoints, and make storage idempotent using the source identifiers plus the observation’s own time or other distinguishing fields. For reproducibility, retain raw pages or enough checkpoint information to resume and investigate a run.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →Use route-specific time rules
Do not assume one universal history window or default. Data API v2 documents different time-window conventions by route; its price-history route also treats zero bounds differently from some other routes. Read the selected route’s start and end parameter rules before backfilling, and record the requested range with the results.
Preserve unavailable values and units
A missing or null numeric value means unavailable, not zero. Keep it null; converting it to zero changes the meaning of the data and can corrupt averages, charts, or downstream comparisons. Also retain units explicitly: bare volume or size values in the Data API are shares, while fields ending in _usdc are USD.
Rank #3
- Fun & Simple Financial Education: Easily grasp stocks, bonds, commodities, and Bitcoin investing through engaging, interactive gameplay. Perfect for teens and adults!
- Ideal Group Size: Designed for 2-6 players, ages 12 and up. Great for family game nights, classroom activities, or friend gatherings.
- STEM-Authenticated & Engaging: Approved by STEM educators, this game offers an addictive learning experience that's both intellectually stimulating and incredibly fun.
- Develop Real-World Skills: Face exciting market scenarios and cryptocurrency challenges to sharpen your decision-making skills in a highly engaging format.
- Play with Purpose: Enjoy an easy-to-learn, captivating game that gives back - a portion of our profits supports Feeding America, adding meaning to your gameplay.
A collector skeleton that does not guess at endpoints
The documentation defines route-specific paths and parameters, but those exact values must be selected from the current endpoint reference for the observation you want. The following Python client is runnable as a pagination and storage starting point once you supply that documented feed URL and its required query parameters. It follows opaque cursors, keeps the query stable, saves raw pages, and does not pretend that every route has the same schema.
import json
import os
import time
from pathlib import Path
import requests
# Set FEED_URL to the exact feed route selected from the current
# Polymarket Data API v2 reference. Do not put secrets in source code.
FEED_URL = os.environ["FEED_URL"]
OUT_DIR = Path("raw_pages")
OUT_DIR.mkdir(exist_ok=True)
# Supply this route's documented filters as a JSON object in FEED_PARAMS.
# Keep these values unchanged throughout the cursor walk.
params = json.loads(os.environ.get("FEED_PARAMS", "{}"))
params.pop("next_cursor", None)
session = requests.Session()
page_number = 0
while True:
response = session.get(FEED_URL, params=params, timeout=30)
if response.status_code == 429:
delay = int(response.headers.get("Retry-After", "1"))
time.sleep(max(delay, 1))
continue
if response.status_code == 503:
delay = int(response.headers.get("Retry-After", "1"))
time.sleep(max(delay, 1))
continue
response.raise_for_status()
payload = response.json()
page_number += 1
(OUT_DIR / f"page-{page_number:06d}.json").write_text(
json.dumps(payload, ensure_ascii=False), encoding="utf-8"
)
# Confirm response keys against the selected route's documented schema.
next_cursor = payload.get("next_cursor")
if next_cursor is None:
break
params["next_cursor"] = next_cursor
print(f"Saved {page_number} raw pages to {OUT_DIR}")For a production collector, add a durable checkpoint for the last cursor and page number, structured logs, bounded retry limits, and a resume path. Confirm whether the chosen route actually uses this cursor shape; the pagination contract is endpoint-specific. Never log credentials if a route requires authentication.
Handle rate limits and failures without corrupting a run
- HTTP 429: Polymarket documents rate limiting with a
Retry-Afterresponse header. Wait for that interval before retrying rather than immediately repeating the request. - HTTP 503: A service-side timeout or unavailable dependency may be involved. The reference says retryable service responses may include
Retry-After; record the status and any trace identifier, then retry according to the response instead of treating it as proof of caller overuse. - Repeated failures: Stop after a bounded retry policy and preserve the last successful cursor. An unbounded loop can conceal a persistent service problem.
- Malformed or partial records: retain the raw response and flag the record for inspection. Do not fill missing numeric fields with zero to make a downstream parser accept them.
The reviewed documentation does not establish one fixed rate limit or a universal retention period for every endpoint. Verify the selected route’s current limits and coverage before committing to a backfill schedule or service-level promise.
Rank #4
- Murphy's Magic Supplies, Inc.
- Magic Shop
- Magic
- Magic Trick
- Wizard
Collecting from Kalshi and comparing venues
Kalshi describes its REST API as providing public market information and order books across markets, along with a limited number of statistics. Its overview does not itself establish a complete endpoint inventory or retention schedule, so choose routes and coverage from the current Kalshi API documentation rather than assuming parity with Polymarket.
Use a venue-specific ingestion layer, then map into a shared schema only where the concepts truly correspond. Similarly worded markets are not necessarily equivalent contracts. Before joining them, compare the event definitions, outcome wording, settlement criteria, timestamps, and price units. Retain venue and original identifiers in the normalized data so the mapping remains traceable.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Keep collection separate from browser screenshots
For structured market data, an API response is the right input: it exposes fields and identifiers that can be stored and interpreted directly. A screenshot records a rendered page, not a structured feed, and cannot replace pagination, typed values, or historical-data semantics. A screenshot can still be useful as a visual record of a page at a particular moment, but do not treat it as a substitute for API ingestion.
The Tool Desk
Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Best Value
- VIBRANT COLOR GAME: Challenge friends and family to connect words with colors in the engaging Hues and Cues, featuring 480 colorful hues for limitless fun!
- FUN FOR ALL AGES: Perfect for family game nights, parties, or casual play, this game brings players of all ages together with simple rules and exciting gameplay.
- UNIQUE EXPERIENCE: No two rounds are the same! Hues and Cues provides a new and unique experience with each playthrough, keeping the fun fresh and engaging.
- CREATIVE AND INNOVATIVE: Use just one or two word clues to guide others to the right hue, sparking creative thinking and fostering fun team interaction.
- QUICK TO LEARN: Hues and Cues offers fast-paced action with easy rules, making it enjoyable for both casual players, and gaming enthusiasts.
Or skip the browser setup
If you need a visual capture rather than structured market records, ScreenshotNeo is a screenshot API and MCP server for developers. One GET request returns a PNG, JPEG, WebP, or PDF; it is not a market-data API. Its clean-shot flow accepts cookie or consent banners and removes known consent platforms, newsletter popups, and chat widgets before capture, with each step configurable. Bot checks, blank pages, timeouts, failed loads, and cache hits are not billed, and responses identify the page verdict and billing status. Its MCP server provides take_screenshot, get_page_info, and capture_pdf for AI agents and MCP clients.
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://polymarket.com -o shot.webpSee the ScreenshotNeo API documentation for request options and response details. Free includes 1,000 shots per month with no card; paid plans start at $5 for 3,000 shots. Sign up for ScreenshotNeo’s free plan.
Common mistakes to avoid
- Using page markup as the primary data source: prefer documented API data models so that the event, market, and outcome relationships are explicit.
- Collapsing identifiers: store event, market, condition, and token IDs separately; use the outcome token ID for outcome-level price and book requests.
- Changing filters during pagination: keep a feed walk’s filters stable and persist cursors, since changing them can re-anchor results.
- Assuming units or default time ranges: check each route’s documentation; shares and USD fields are not interchangeable, and history windows are route-specific.
- Joining markets by title alone: compare settlement rules and contract definitions before treating markets on different venues as equivalent.
- Turning missing into zero: null means unavailable in the documented Data API semantics, not an observed zero.
Sources and scope
The platform descriptions and endpoint behaviors above reflect the official Polymarket Market Data Overview, Polymarket Data API v2 reference, Polymarket trading quickstart, and Kalshi Help Center article “Kalshi API” dated March 10, 2026. Quotas, route availability, and history coverage can change; the documentation for the particular endpoint remains the authority for an implementation.
Frequently Asked Questions
Does reading public market data require trading authentication?
Not necessarily. Public market-data reads and account or trading operations are separate API use cases; follow the authentication requirements documented for the particular route.
Free tools Windows power users keep installed
One-click scans. No signup required.
Can I assume Polymarket and Kalshi price values are directly comparable?
No. Establish common units and confirm that the contracts’ outcome wording and settlement conditions match before comparing or joining observations.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
