Compare the top 5 platforms similar to The Overround. Match on features, US legality, and crypto support to find the right fit for your trading style.
Ranked by shared features with The Overround. Last updated October 2026.
Cobia is the data, models and graded track record that sit on top of Polymarket and Kalshi — not another exchange. One screen: live picks, a Vegas engine, cross-venue line-shopping, smart-money tracking and our own trained per-game models, every pick graded from the settled outcome with ROI beside hit rate.
Sonist automates live mention-market trading on Kalshi and Polymarket. It brings markets from both exchanges into one interface and monitors live audio, subtitle feeds, or accessibility captions for configured words. When a word is said, Sonist applies your risk limits and sends the trade through your account, letting you use the lowest-latency source available for each event and guaranteeing profit.
Independent analysis and quant tooling for Kalshi, Polymarket, DraftKings Predictions and FanDuel Predicts, published by the analyst collective The 7 Oracles. 25 quant tools on the site, most of them free: EV calculator, Kelly sizing, probability/odds conversion, Bayesian updater, base-rate scanner, a fully-free combo edge builder with a 7-tier verdict ladder, KL-divergence, a cross-platform Kalshi/Polymarket arbitrage scanner, a daily mispricing scan, commodity and metals edge signals driven by options-implied volatility, NFL power ratings and win probability, and a state-by-state legality map. The same engine is exposed to AI agents as a Model Context Protocol server — 23 tools callable from Claude, ChatGPT and Cursor, 16 of them with no API key. Coverage is numbers-first and calibrated: model-vs-market reads, a published graded track record on every signal feed, and explicit methodology on every tool. Prediction markets are treated as event derivatives rather than as a sportsbook — trader, position, contract. Free tier includes the newsletter, daily movers and email-gated tools. Pro is $14.99/mo or $150/yr.
Spectral Edge is a suite of trading signals built specifically for BTC prediction markets using physics-trained AI. SpectralBot reads every BTC 15-minute prediction market in real time and delivers a clear UP or DOWN signal every 5 seconds. Start with a free trial.
The Overround compares the same event across Kalshi, Polymarket and a panel of nine US sportsbooks, normalises the prices so they can be read against each other, and shows which venue is cheapest to back a given side. It also publishes the overround on each market, the sum of what it costs to back every outcome at each venue, so you can see what the house is charging before you trade. Every market gets its own page carrying the full field, the settlement source and the contract terms. Free, no account, and the underlying data is available as unauthenticated JSON.
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