Make the numbers behindevery position explicit
Compare your forecast with the market, quantify expected value, and turn an edge into a deliberate position size. These calculators and guides help you evaluate the trade before you place it.
Start with the input you have
Have a prediction-market share price? Use the EV & Kelly calculator. Have decimal or American odds? Use the odds edge calculator. You can also monitor large trades with Whale Watch or unpack the sizing method in the Kelly Criterion guide.
Prediction Market EV & Kelly Calculator
Compare a YES share price with your probability estimate, then see the edge, expected value, ROI, and a Kelly-sized stake for your bankroll.
Calculate a position →Betting Odds Edge Calculator
Use decimal or American odds with your win-probability estimate to calculate expected value and the full-Kelly bankroll fraction.
Check the odds →Kelly Criterion Learning Hub
See the Kelly formula in context, work through examples, and understand why many traders reduce the suggested full-Kelly stake.
Learn Kelly sizing →Market-Moving Events Calendar
Follow countdowns to economic releases, central-bank decisions, elections, and other catalysts that can move market prices.
See upcoming events →Polymarket Strategy Guide
Build your foundation in market mechanics, order books, automated market makers, risk, and hedging before putting capital to work.
Explore the strategy guide →Put a clear process behind every trade
Learn how prediction markets work, then use live market data to find opportunities worth evaluating with these tools.