Learning Center
Plain-English guides to every tool and the math behind them: how fair prices are built, why the vig matters, how to size bets, and how to read every number on the screen.
Start here: fundamentals
The math every tool is built on.
Intro to +EV betting Positive expected value means a price pays more than its fair odds. Here's how to find the fair odds and what the edge really means.4 min readDevig methods compared: multiplicative, additive, power, Shin, probit Five ways to take the vig out of a price, when they agree, when they don't, and which one we use by default.4 min readBankroll and Kelly: how much to bet on an edge Kelly sizes a bet by its edge and its odds. Most people should bet a fraction of it, with a cap.4 min readExchange fees: your net price on Kalshi, Polymarket, Novig and more Exchanges charge fees instead of building vig into the price. Here's how each venue's fee changes the odds you actually get.4 min readWhy closing-line value matters The closing price is the market's best estimate. Beating it consistently is the clearest early sign that your edges are real.4 min read
Tool guides
How to read each screen, with worked numbers.
How to read the Odds Screen Every book's pregame price side by side, with the best net price marked and a no-vig fair line next to it.3 min readHow to use the +EV finder: Props, Game Lines and Sniper One screen with three presets that ranks every price at your books against a fair price built without that book.4 min readFair value and devig settings explained How the Fair value & filters sheet decides which books build the fair price, how the vig comes off and which rows you see.4 min readArbitrage: back every side and lock the return When the best prices on every outcome add up to less than 100%, the right stakes return the same amount whatever happens.4 min readLow hold: the cheapest markets on the board The combined vig of the best price on each side tells you how cheap a market is to bet both ways.4 min readMiddles: when both sides of a bet can win Take the Over at a low number and the Under at a higher one. If the result lands between them, both bets cash.4 min readProp discrepancies: lines hung away from the market When one book or pick'em app posts a player line away from everyone else's, the fair ladder tells you what that gap is worth.4 min readPick'em optimizer: pricing PrizePicks, Underdog and Dabble Each app's payout table sets the win rate every leg needs. Fair probabilities from the betting market tell you which legs clear it.5 min readWhale Watch: large prediction-market trades, in context Coming soonBig fills on Kalshi and Polymarket, matched to the best retail price still available, with every signal logged and graded.3 min readHow the Futures screen prices a whole field Every book's price on each runner of a futures market, with a no-vig fair built from the whole field and each book's real margin.5 min readDiscord alerts: what's planned and how thresholds will work Coming soonMembers-only Discord alerts for new edges, informational only, rate-limited, with your own thresholds per alert type.3 min readBet tracker and closing-line value Coming soonLog the price you took, compare it with the closing fair price, and learn whether you're beating the market before results can tell you.3 min read
Prefer to try it?
The calculators run the same math as the tools, free and without an account.