Risk of Ruin

Probability of losing your full bankroll under flat-bet, infinite-time advantage play.

BJ basic ≈ 1.15
Units: 400
Risk of ruin
0.2360%
Conservative — under 1%.

Math

Brownian (continuous) approximation: RoR = exp(−2 · μ · B / σ²) where μ is per-bet edge, σ is per-bet std dev, and B is bankroll in units (bankroll ÷ bet size).

The formula assumes flat bets, positive edge, and infinite play. In real play you stop at a target or a loss limit, which lowers RoR but introduces other tradeoffs (you also stop winning at the cap).

For zero or negative edge, the formula collapses to certain ruin (1.0).