Kelly Criterion Calculator
Apply the Kelly formula to any price and probability estimate.
Kelly Fraction
8.33%
Full Kelly Amount
$83.33
Expected Value
+12.50%
Fractional Kelly Options
Fractional Kelly scales the full Kelly result down to reduce variance.
| Strategy | Fraction | Stake | % of Bankroll |
|---|---|---|---|
| Full Kelly | 1x | $83.33 | 8.33% |
| Half Kelly | 0.5x | $41.67 | 4.17% |
| Quarter Kelly | 0.25x | $20.83 | 2.08% |
| Eighth Kelly | 0.125x | $10.42 | 1.04% |
How It Works
The Kelly Criterion gives the bankroll fraction that maximizes long-term growth, based on the gap between the price and the probability estimate.
f* = (bp - q) / b Where: f* = fraction of bankroll to wager b = decimal odds - 1 (net odds) p = probability of winning q = probability of losing (1 - p)
See how we compare: vs The Odds API · vs BetsAPI · vs OpticOdds