Kelly Criterion Calculator
Works out the stake that maximises long-term growth on paper.
Kelly fraction
— %
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Half Kelly — %
Expected return per 1 staked —
Reading this —
The formula
f = p − (1 − p) ÷ b
It maximises long-run growth given the odds. Errors in your estimate of p move the answer a lot.
What to watch out for
It is a mathematical result, not a recommendation to bet or trade.
Frequently Asked Questions
What is the Kelly criterion?
A formula for sizing bets. A 55% chance of winning 1.5 per 1 risked gives 25.00%.