Bankroll Calculator
How much money do you actually need to play your stakes without going broke?
Every serious grinder wrestles with the same question: how much is enough? Too little and variance eats your roll before your skill edge compounds. Too much and you’re under-rolled at the wrong stakes and leaving money on the table.
The math isn’t complicated. For a normally-distributed per-hand return with win rate μ and standard deviation σ, your risk of going broke with bankroll B is:
$$RoR = e^{-2 \mu B / \sigma^2}$$
Solve for B and you get the minimum bankroll that keeps your risk of ruin at your chosen level. The tool below does it with your actual numbers.
What to put in
- Win rate (BB/100) — your tracked win rate, not your aspirational one. Use 10k+ hands of real data, or 0 if you haven’t tracked.
- Standard deviation (BB/100) — from your tracking software. If you don’t have one, live NL cash is typically 80–120 BB/100. Online 6-max cash is 90–110.
- Risk of ruin (%) — 5% is aggressive, 1% is standard, 0.5% is conservative. Pick 1% unless you have a specific reason.
What it doesn’t account for
Tilt, game selection drift, and the fact that your real distribution has fatter tails than a normal curve. Treat the output as a floor, not a ceiling. And if your win rate is negative, the formula returns nothing useful — no bankroll saves a losing strategy.
Bankroll Calculator
Formula: B = −ln(RoR) · σ² / (2μ). Assumes a normal-distributed
per-hand return with the stats you entered. In real play, run-it-twice, tilt,
and game selection drift matter too — this is a floor, not a ceiling.