Bankroll Calculator

How to Calculate Your Poker Bankroll

Proper bankroll management is the single most important discipline for long-term poker success. Even winning players can go broke without sufficient bankroll to weather the inevitable downswings.

The Risk of Ruin Formula

This calculator uses the risk of ruin formula to determine the minimum bankroll needed:

Bankroll = (SD² ÷ (2 × WR)) × ln(1 ÷ RoR)

Where SD is your standard deviation, WR is your win rate, and RoR is your acceptable risk of ruin expressed as a fraction (5% = 0.05). For cash games, SD and WR are in bb/100 and the result is in big blinds (100bb per buy-in). For tournaments, enter ROI and standard deviation as percentages per tournament and the same formula returns the answer directly in buy-ins, since the normal-approximation bb/100 model does not capture top-heavy MTT payout variance.

Key Factors

• Win Rate: Your expected profit per 100 hands. Higher win rates require smaller bankrolls.
• Standard Deviation: A measure of variance. Higher variance games (PLO, tournaments) require larger bankrolls. Typical values: 60-100 bb/100 for cash games.
• Risk of Ruin: The probability you'll lose your entire bankroll. 1-5% is standard for professional players.

Cash Games vs. Tournaments

Tournaments have much higher variance than cash games due to top-heavy payout structures and the all-or-nothing nature of each event. This means tournament players need significantly larger bankrolls — typically 100+ buy-ins compared to 20-50 for cash games.