Kelly Criterion Calculator

What is the Kelly Criterion?

The Kelly Criterion is a mathematical formula used to determine the optimal size of a series of bets to maximize long-term growth of your bankroll. It considers both the odds offered and your estimated probability of winning to calculate the ideal stake size as a percentage of your current bankroll.

This formula helps bettors avoid betting too much (which risks significant losses) or too little (which limits potential gains). The Kelly Criterion is particularly useful for professional bettors and those serious about long-term profitability in sports betting.

How to Use This Calculator:

1. Enter the american odds offered by the bookmaker
2. Input your estimated probability of winning (as a percentage)
3. Enter your current bankroll size
4. The calculator will show your optimal bet size and other relevant information

Benefits of Using Kelly Criterion

• Optimal bankroll growth over time
• Systematic approach to bet sizing
• Protection against excessive losses
• Mathematical foundation for betting decisions

Important Considerations

• The Kelly Criterion assumes accurate probability estimates
• Many professional bettors use "Fractional Kelly" (25-50% of the suggested bet) for safety
• Results are highly sensitive to probability estimates
• Best used as part of a comprehensive betting strategy

Note: The Kelly Criterion is a tool for guidance. Consider using a fractional Kelly approach (betting a fraction of the recommended amount) to reduce variance and risk.