Poker Bankroll Calculator

Risk of ruin from your win rate · move-up and move-down rules · downswing simulator

Currency Game format

1 Your game

Buy-in Buy-in in big blinds Win rate Standard deviation Volume per month Your bankroll

Win rate and standard deviation are in the units shown in the labels. Take them from your tracker or results; the format defaults are only starting points.

2 Risk of ruin

Risk of ruin

Bankroll in buy-ins

Expected per month

Monthly swing (1 SD)

Chance of a losing month

Target risk of ruin

Bankroll for that target

That is, in buy-ins

Short by / extra

Risk of ruin = e^{−2 × win rate × bankroll ÷ variance}: the chance of ever losing the whole bankroll if your win rate and standard deviation stay the same, results are roughly normal and you never move down. It is an estimate, not a promise.

Rule-of-thumb bankroll the quick estimate by buy-ins

Sessions per month

Aggressive

Balanced

Conservative

Monthly exposurebuy-in × sessions

Your bankroll coversbuy-ins

Rules of thumb: 20, 40 or 60 buy-ins for cash games and double that for tournaments. They ignore your actual win rate, which the risk-of-ruin figure above uses.

3 Move-up and move-down rules

Next level buy-in Move up with this many buy-ins of the next level Drop down below this many buy-ins of this level Level below, buy-in

Move up at

Drop down at

Risk of ruin one level upsame win rate, bigger stakes

4 Downswing simulator 100 random runs from your numbers

Length of each run

Simulated runRun that went brokeMedian runStarting bankroll

Runs that went broke

Median end bankroll

Worst 5% end below

Typical worst downswing

Runs that ended below start

Each run adds random results with your win rate and standard deviation. Different runs from the same numbers can look very different; that spread is variance.