Kelly Criterion Calculator
The Kelly Criterion helps you determine the mathematically optimal stake size to maximise long-term growth. It balances risk and reward based on your edge.
Results
10.00%
Kelly Stake %
$100.00
Recommended Stake
$10.00
Expected Value
$50.00
Half Kelly (safer)
What is the Kelly Criterion?
The Kelly Criterion is a formula developed by John L. Kelly Jr. in 1956 to determine the optimal size of a series of bets. It maximises the expected logarithm of wealth, which translates to the fastest long-term growth rate.
Formula: f* = (bp - q) / b, where b = decimal odds - 1, p = probability of winning, q = 1 - p.
Many professional punters use "Half Kelly" (staking half the Kelly amount) to reduce variance while still capturing most of the growth advantage.
This calculator is for informational purposes only. Always check current odds with your bookmaker. Gamble responsibly.
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