Kelly Criterion Calculator
Calculate optimal bet sizing using the Kelly Criterion formula for maximum long-term growth
Kelly Calculator
Enter your odds and win probability to calculate optimal stake
100%
1%50%100%
(80%+ Very High Risk)
Results
Enter odds and win probability to see results
How to Use the Kelly Criterion Calculator
Step 1: Select Odds Format
Choose your preferred odds format:
- • Decimal: 2.50 (common in Europe)
- • Fractional: 3/2 (common in UK)
- • American: +150 (common in US)
Step 2: Enter Your Odds
Input the odds offered by the bookmaker for your selected bet.
The calculator will automatically convert between formats for internal calculations.
Step 3: Estimate Win Probability
Enter your estimated probability of winning (0-100%).
This is your edge - how likely you think the outcome is to occur based on your analysis.
Step 4: Set Kelly Percentage
Use the slider to set what percentage of the full Kelly stake you want to bet.
Most professional bettors use 20-50% Kelly to reduce variance.