Bankroll Management Calculator
Calculate optimal bet sizing with Kelly Criterion, track expected value, and assess your risk of ruin. The most important tool in sports betting — free.
Your Betting Setup
Kelly Criterion Recommendation
Half Kelly is recommended for most bettors. It captures 75% of the growth rate with significantly lower variance and risk of ruin.
Risk Assessment
Estimated risk of losing your entire bankroll at current unit size. Your bankroll management is conservative — low risk.
Why Bankroll Management Matters More Than Picks
A bettor with 55% accuracy and proper bankroll management will outperform a bettor with 60% accuracy who bets randomly. That sounds counterintuitive, but the math is clear: inconsistent sizing exposes you to ruin even with an edge. Professional bettors treat bankroll management as the foundation of everything else. The picks matter, but only if you survive long enough to see the edge play out over hundreds of bets.
The Kelly Criterion Explained
The Kelly Criterion was developed by John Kelly at Bell Labs in 1956. It determines the mathematically optimal bet size to maximize long-term bankroll growth. The formula accounts for both your edge (how often you win vs. the odds) and the payout. Full Kelly is theoretically optimal but produces high variance. Most professionals use half Kelly, which captures 75% of the growth rate with significantly less volatility. Our AI prediction models provide win probabilities you can plug directly into the Kelly formula to calculate optimal sizing for every bet.
Unit Sizing Guidelines
| Style | Unit Size | $1,000 Bankroll | Risk Level |
|---|---|---|---|
| Conservative | 1% | $10/bet | Low |
| Moderate | 2% | $20/bet | Low-Medium |
| Aggressive | 3-5% | $30-50/bet | Medium |
| Reckless | 10%+ | $100+/bet | High |
Bankroll Management FAQ
What is the Kelly Criterion?
A formula that calculates optimal bet size based on your edge and odds. f* = (bp - q) / b. Most pros use half Kelly for safety.
What unit size should I use?
1-3% of your bankroll per bet. Conservative: 1%, moderate: 2%, aggressive: 3-5%. Never exceed 5% on a single wager.
What is risk of ruin?
The probability of losing your entire bankroll. Smaller unit sizes dramatically reduce it. At 1% units with a 55% win rate, risk of ruin is nearly zero.
Get AI Win Probabilities for Kelly Sizing
Plug our AI-generated win probabilities directly into the Kelly formula. NFL, NHL, Tennis, and March Madness — 99¢ per sport, lifetime access.
Get AI Predictions — 99¢ Each