Bankroll Simulator
Monte Carlo simulation: see how your edge plays out over thousands of bets. Visualize variance and risk of ruin.
What This Simulator Shows
This Monte Carlo simulation runs your betting parameters thousands of times to show the range of possible outcomes. Even with a proven edge, short-term results vary wildly due to variance.
💡 Key Insight: Variance Is Real
A 55% win rate at -110 odds has +2.5% EV per bet. Over 500 bets, you expect to profit ~25% of your bankroll. But the simulation shows you might be up 80%... or down 20%. Both are possible even with an edge.
- Multiple paths: Each line on the chart is one possible future. Your actual results will be one of these paths.
- Risk of ruin: % of simulations where bankroll dropped below your threshold. This is your "blowup" risk.
- Percentiles: 5th percentile is your worst 5% outcomes. 95th is your best 5%. Plan for the bad scenarios.
How to Use This Tool
- Enter your win probability — be honest. If you're betting -110 and winning 53%, enter 53%.
- Set your bet sizing — 1-2% of bankroll is conservative, 5%+ is aggressive.
- Run the simulation and look at the 5th percentile — can you survive that outcome?
- If risk of ruin is >5%, reduce bet sizing or increase bankroll.
Understanding the Results
📈 Expected Value vs Reality
EV is what happens in the infinite long run. In 500 bets, you're nowhere near infinity. The median outcome is usually close to EV, but individual paths can deviate wildly. This is why bankroll management matters more than picking winners.
🎯 Kelly Criterion Connection
The Kelly Criterion calculates optimal bet sizing. If Kelly says bet 5% but you're betting 10%, run this simulation to see your risk of ruin. Overbetting destroys bankrolls even with a proven edge.