// CALCULATORS
Betting calculators.
Working math, on desk.
8 interactive tools for odds, edge, stake sizing, and juice. Every one is free, runs on this page, and is linked from the article that teaches the concept behind it.
Starters
Four tools most new bettors open first. Use one before your next wager.
Implied Probability Converter
Convert American, decimal, and fractional odds. See the implied probability and the book's hold on a two-sided market.
Open toolExpected Value Calculator
Estimate the expected value of a bet given the odds offered and your fair-probability estimate. The number that decides whether a bet is worth placing.
Open toolKelly Criterion Calculator
Compute full and fractional Kelly bet sizes from your edge and your bankroll. The formal answer to how much to risk on a positive-EV bet.
Open toolJuice Impact Calculator
How much does -110 cost over a year of betting? See the compounding effect of juice and the difference reduced juice (-105) makes across thousands of bets.
Open toolAll calculators
Parlays, public bias cost, line movement, and trap-line drills. Together with the starters above, that is the full set of 8 registered tools.
Sportsbooks
Public Bias Cost Calculator
Quantify the structural cost of betting popular favorites and overs. The shading premium accumulates; this tool shows you how much across a season.
Open toolLine Movement Explorer
Walk through the four causes of line movement (information, sharp action, public volume, cross-market hedging) interactively. See how each pattern reads on the screen.
Open toolTrap Line Spotter
Practice identifying trap-line signatures from realistic example matchups. Sharpen the pattern recognition that the framework articles describe.
Open tool