Betting Strategy Simulator

Understanding Betting Strategy Simulation

This advanced simulator helps you understand the real-world implications of different betting strategies before risking real money.

Why Monte Carlo?

Unlike simple expected value calculations, Monte Carlo simulation accounts for variance and path dependency. It shows you not just the average outcome, but the full range of possibilities including rare but devastating losing streaks.

Key Risk Metrics

• Risk of Ruin: Probability of losing your entire bankroll. Even 5% is significant over thousands of bets.
• Maximum Drawdown: The largest peak-to-trough decline. Psychologically important for staying the course.
• Losing Streaks: Long losing streaks are inevitable. Plan your bankroll to survive them.

Practical Advice

• Kelly Criterion is theoretically optimal but can be aggressive. Consider using half-Kelly (0.5 fraction) for more conservative growth.
• Martingale and Fibonacci can seem safe in short runs but have catastrophic long-term failure rates.
• Flat betting is boring but reliable. If you have a positive edge, it will eventually show in the results.

Common Mistakes

• Using full Kelly criterion without accounting for estimation errors in your win rate — if you overestimate your edge by even 2%, full Kelly can lead to aggressive overbetting. Half-Kelly or quarter-Kelly is almost always safer and still captures most of the growth advantage.
• Running too few simulations and drawing conclusions from noisy results — 100 simulations is not enough to estimate tail risks like bust probability accurately. Always run at least 10,000 simulations, and preferably 50,000+ for reliable percentile estimates.
• Ignoring the psychological impact of drawdowns — your strategy is only useful if you can actually stick with it through losing periods. If a 20% drawdown would cause you to abandon the strategy, choose a more conservative staking plan even if it sacrifices some expected growth.

Worked Examples

Flat Staking Strategy Simulation

Enter a $1,000 starting bankroll, flat staking at $50 per bet, 55% win rate, and average odds of 1.90. Run 10,000 simulations of 1,000 bets each. The calculator shows a median ending bankroll of approximately $1,450, with a 5th percentile outcome of around $650 and a 95th percentile of $2,350. The bust probability (reaching $0) is approximately 3%. Flat staking provides steady, predictable growth with low ruin risk — ideal for conservative bettors.

Kelly Criterion vs Flat Staking

Using the same parameters (55% win rate, 1.90 odds, $1,000 bankroll), switch to Kelly staking. Full Kelly suggests a 5.26% stake per bet. The simulator shows a median ending bankroll of approximately $2,800 — nearly double flat staking — but with a 5th percentile of just $280 and much wider variance. Half-Kelly (2.63% per bet) gives a median of $1,900 with a 5th percentile of $520, offering a better balance between growth and safety.

Understanding Realistic Drawdowns

Even with a genuine 55% win rate at 1.90 odds, losing streaks happen. The simulator shows that a 10-bet losing streak occurs with about 3.4% probability in a 1,000-bet sequence — roughly once every 30,000 bets. A 15-bet streak is rare (0.01%) but not impossible. With flat $50 stakes, a 10-bet streak costs $500 (50% of a $1,000 bankroll). Use these results to set realistic stop-loss levels — if your actual drawdown exceeds the 99th percentile from the simulation, it may signal a real edge deterioration rather than normal variance.