Betting SystemsAdvanced

Kelly Criterion

Mathematical formula to calculate optimal bet size based on edge and odds

Definition

The Kelly Criterion is an advanced mathematical formula that calculates the theoretically optimal bet size to maximize long-term growth of your bankroll. It considers your probability of winning (edge) and the payout odds. Formula: (BP - Q) / B, where B = odds, P = win probability, Q = loss probability. In practice, most gamblers use 'fractional Kelly' (25-50% of the calculated amount) because full Kelly can be too aggressive and volatile.

Example

If you estimate 55% chance to win with 2:1 payout: Kelly = ((2×0.55) - 0.45) / 2 = 0.325 or 32.5% of bankroll. Since this is extremely aggressive, most use 1/4 Kelly = 8.1% of bankroll. With $1000, that's an $81 bet.

💡Strategy Tip

⚠️ Advanced users only. Kelly requires accurate estimation of your win probability, which is nearly impossible in Aviator. Most professionals use 1/4 to 1/2 Kelly to reduce volatility while maintaining growth potential.