Tools > Bankroll Requirement & Risk of Ruin

Bankroll Requirement & Risk of Ruin

Plan how big a roll a given win rate and swings actually demand. Forward-looking companion to the session tracker.

Win rate (bb / 100 hands)

Std deviation (bb / 100)

Big blind ($)

Current bankroll ($)

Acceptable risk of ruin

Recommended bankroll for target risk—

= buy-ins (100bb)—

Risk of ruin at current bankroll—

Verdict—

Model: continuous-approximation risk of ruin RoR = exp(-2·WR·B / SD²), where B is bankroll in bb. Assumes win rate holds and no bet-sizing changes. A positive win rate is required — a break-even or losing player will eventually go broke at any bankroll.