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Kelly Criterion
Calculate optimal bet sizing based on your edge and bankroll
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The odds you're getting from the book
Your estimated probability of winning
Reduce variance with fractional Kelly
Results
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About Kelly Criterion
The Kelly Criterion is a formula for optimal bet sizing that maximizes long-term growth while minimizing risk of ruin. Full Kelly can be volatile, so many bettors use fractional Kelly (e.g., half Kelly) to reduce variance. The formula requires accurate probability estimates — overestimating your edge leads to overbetting.