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Calculate a stake from your estimated edge and bankroll.
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The Kelly criterion sizes a stake to maximize long-term bankroll growth for a given edge and payout. Enter your estimated win probability, the odds, and your bankroll, and the calculator returns the Kelly stake, including a fractional option for reduced variance.
A staking formula that recommends the bankroll fraction to bet when you hold an edge, balancing growth against the risk of drawdowns.
Most bettors use quarter or half Kelly. Full Kelly maximizes growth but swings violently, and your probability estimates are never exact.
Overbetting with an inflated edge is the main way Kelly hurts a bankroll. Fractional staking is the standard protection against estimation error.