What is the best free tool stack for prediction market trading?

The stack community roundups keep recommending: Polymarket Analytics to see who is actually winning, Polysights for AI-assisted market analysis, and Polylerts for free Telegram alerts when top wallets move. Add the free DefiRate calculator suite for fee and EV math, and a free cross-venue terminal like Kairos to trade Kalshi and Polymarket from one book.

Is there one tool that shows Kalshi and Polymarket together?

For viewing odds side by side, Oddpool and Prediction Hunt compare venues. For actually trading them together, Kairos aggregates Kalshi, Polymarket and Predict.fun into one live order book with sub-second data. No tool yet tracks your combined portfolio P&L across venues automatically; that remains the biggest gap in the landscape.

Are there good tools for Kalshi specifically?

Fewer than for Polymarket, because Kalshi trades are anonymous and its leaderboard is opt-in, which limits what third parties can build. Lychee Data covers Kalshi historical data, OddsAssist has a free Kalshi fee calculator, TrendSpider ships a Kalshi indicator suite, and cross-venue terminals like Kairos include Kalshi's full book. Treat any third-party Kalshi leaderboard with care: they are built from small opt-in pools, not the exchange's actual top traders.

Do prediction market tools cost money?

The essentials are free: venue leaderboards, DefiRate's 13 calculators, EventArb's arbitrage calculator, Polylerts alerts, Dune dashboards, and the Kairos terminal. Paid tiers cluster around copy trading ($20 to $30 a month), arbitrage scanning ($9 a week to $59 a month), and historical data (subscription pricing).

Best Prediction Market Tools (2026)

Every tracker, arb finder, calculator, alert bot and tax tool worth knowing for Polymarket and Kalshi traders. Prices and claims verified against the live sites.

Updated August 30, 2026 · every price checked against the live site

Short answer: there are 170+ tools and most traders need five: Polymarket Analytics for who wins, Polylerts for alerts, DefiRate for the math, Oddpool to compare venues, and Kairos, the free a16z-backed terminal, to execute across every venue from one book.

The directory

32 tools · filter by category

Kairos Cross-venue trading terminal: Kalshi, Polymarket and Predict.fun in one order book, with sub-second data and advanced order types. K + PM + Predict.funfreea16z-backed
Polymarket Analytics 1M+ wallets ranked by P&L, win rate and streaks, refreshed every 5 minutes. The category leader. Polymarketfree$20/mo premium
Polymarket leaderboard The official profit and volume rankings, also exposed through a public API endpoint. Polymarketfree
Polycopy Copy trading on a leaderboard: Copy Score net of costs, automated trader bots with stop-losses. Polymarketfree tier$30/mo + 0.5%
Hashdive One of the few dual-venue trackers: Smart Score ratings, whale feed, insider detection, screeners. PM + Kalshifree
KalshiSpy Surfaces verified profitable Kalshi traders' open positions and builds a consensus view. Kalshi$61/mo
PredictFolio Free blockchain-based trader and portfolio analytics; a reference for data accuracy. Polymarketfree
polymarket-whales Open-source Python CLI that watches order flow and pings Telegram on threshold-size trades. PolymarketOSS
Dune dashboards Community SQL dashboards: venue volumes, open interest and users across Polymarket, Kalshi, Limitless. cross-venuefree
PolymarketData Historical infrastructure: minute-level prices and L2 order book snapshots, 19B+ rows, API and bulk S3. Polymarketpaid tiers
Lychee Data The Kalshi historical answer: 36GB+ of trades and order books with no-code charting and backtesting. Kalshifree + paid
Kalshi Pro Kalshi's own power-user interface: real price and volume charts, live trade-by-trade view. Kalshifree
TrendSpider Kalshi suite The only charting-platform integration in the space: live Kalshi odds as chart indicators. Kalshiwith sub
Polysights AI-assisted dashboard: market summaries, insider-activity signals, Telegram alerts, 30+ metrics. Polymarketfreemium
EventArb Free manual arb calculator with fee-adjusted risk-free setups, plus email alerts. K + PM + Robinhoodfree
ArbBets 990+ matched market pairs, claims 100+ arbs daily at 2 to 8% spreads, API access. PM + K + Opinionfrom $59/mo
ArbiTrack Scanner refreshing every 3 minutes, flags 5 to 20 cent gaps across three venues. PM + K + PredictItfree tier$19/mo
Prediction Hunt Live odds from six venues in one view and one API call. 6 venuesfree core
Oddpool The most direct Kalshi vs Polymarket comparison: divergence tracking with fee context, plus a real data API underneath. PM + Kalshifree tier$30/mo
DefiRate Fed odds Fed-decision lines side by side with fee-adjusted expected earnings per contract. PM + Kalshifree
event-contract-arbitrage Open-source arb scanner if you would rather run your own. K + PM + RobinhoodOSS
DefiRate calculators 13 free calculators: odds conversion, EV, fees, Kelly, hedging, parlays, Monte Carlo bankroll simulation. 10 platformsfree
OddsAssist Kalshi calcs Kalshi fee calculator with maker and taker sides (maker orders cut fees roughly 4x), plus payout calculators. Kalshifree
Prediction Markets Picks 25+ quant tools: Kelly, EV, Bayes updater, correlation-adjusted parlay edges, even an MCP server for AI assistants. cross-venuefree$14.99 pro
Prediction News Dedicated industry newsroom: regulation, funding, platform changes, market data. industryfree
Adjacent News News wired to markets, with data APIs across 40K+ markets. cross-venuefree tier
Polylerts Telegram alerts when the top 0.5% of Polymarket wallets trade; community-run. Polymarketfree
PolyAlertHub Whale, insider and market alerts via email and Telegram. Polymarketfree basic
Polymarket Alerts Price-change, resolution and whale alerts with iOS and Android apps, no login needed. Polymarketfree
Awaken Tax Crypto tax software with real Polymarket support: matches redemptions to cost basis, books losing resolutions as losses. Polymarketpaid
Manage Bankroll Manual cross-platform bankroll and P&L tracking spanning Kalshi, Polymarket, sportsbooks and brokers. 25 platformsfree to 50 txns$100/yr
TraderTax calculator Free 2026 calculator comparing capital, 60/40 and gambling tax treatments side by side. US taxesfree

Field notes

what the tool pages will not tell you

Caveat · Kalshi leaderboards

Kalshi trades are anonymous and its native leaderboard is opt-in, with users opted out by default. Every third-party "Kalshi leaderboard" is built from a small opt-in pool connected to that service, not the exchange's actual top traders. Read Kalshi copy-trading claims with that in mind.

Caveat · taxes

Kalshi issues no 1099-B for event-contract trades, Polymarket issues no US tax forms at all, and every USDC entry and exit on Polymarket is its own crypto disposal. How the IRS classifies prediction-market income is genuinely unsettled. Keep records from day one.

The gaps nobody has filled

open problems · august 2026

Cross-venue portfolio P&L

No tool automatically aggregates live positions across Kalshi and Polymarket into one P&L. Everything is manual entry or single-venue.

still open

Kalshi tax integration

Polymarket has Awaken and Blockpit; Kalshi has export-and-spreadsheet.

still open

Kalshi trader transparency

Anonymity plus an opt-in leaderboard means the Polymarket-style copy-trading economy cannot exist there yet, whatever the marketing says.

still open

Charting integrations

One TrendSpider suite; otherwise nothing connects prediction markets to mainstream charting.

still open

find the edge→size it→time it→execute

Trackers find the edge. Calculators size it. Alerts time it.

When it is time to execute, the free Kairos terminal trades Kalshi, Polymarket and Predict.fun from one book.

FAQ

What is the best free stack?

Polymarket Analytics for who is winning, Polylerts for when they move, Polysights for AI-assisted analysis, DefiRate for the math, and Kairos to execute across venues. Total cost: zero.

Is there one tool that covers Kalshi and Polymarket together?

For viewing, Oddpool and Prediction Hunt. For trading, Kairos aggregates both plus Predict.fun into one order book. For portfolio tracking, nothing automatic exists yet.

Why are there so many more Polymarket tools than Kalshi tools?

Data access. Polymarket's activity is public on-chain, so anyone can build a tracker. Kalshi trades are anonymous with an opt-in leaderboard, which caps what third parties can see and build.

Do I need paid tools?

Not to start. The free stack covers analysis, alerts, math and execution. Paid tools earn their keep in automated copy trading, always-on arb scanning, and deep historical data.