Kelly Criterion Calculator: Optimal Bet Sizing

Calculate the mathematically optimal stake size for any bet using the Kelly Criterion. Enter your bankroll, the decimal odds offered, and your estimated true probability of winning. Half-Kelly is recommended for most bettors to reduce variance.

Free Kelly Criterion calculator for sports betting. Calculate optimal stake size based on your bankroll, decimal odds, and estimated true probability. Includes half-Kelly and quarter-Kelly options for variance reduction.