Find the best amount to bet based on your advantage and how much money you have. Bet less to be safer.
Enter fraction (0-1) or percentage (0-100) to scale the full Kelly stake.
The Kelly Criterion is a formula that determines optimal bet sizing to maximize long-term bankroll growth while minimizing risk of ruin. It tells you exactly what percentage of your bankroll to wager based on your edge.
Most sharp bettors use "fractional Kelly" (25-50% of full Kelly) to reduce variance. Full Kelly is mathematically optimal but extremely volatile—a few bad beats can wipe out significant bankroll. Quarter Kelly grows slower but sleeps better.
Kelly only works if your edge estimate is accurate. Overestimating your edge leads to overbetting and potential ruin. When uncertain, bet smaller. It's better to leave money on the table than go broke.
