Kelly Criterion Calculator

Calculate the optimal bet size based on your edge and bankroll.

Odds

True probability (%)

Bankroll ($)

Kelly fraction (1 = full, 0.5 = half)

Recommended stake

$50

5.0% of bankroll

How it works

Optimal fraction of bankroll = edge / decimal_odds-1. Full Kelly maximizes growth but is high variance. Half Kelly (fraction=0.5) is the practical sweet spot.

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