Poker
Poker Variance Calculator
Estimate poker session mean, standard deviation and an approximate 95% outcome interval from your entered win rate, deviation per 100 hands and hand count.
Your result
$500.00
Modeled mean session profit
- Session standard deviation
- $800.00
- Approximate 95% lower outcome
- −$1,068.00
- Approximate 95% upper outcome
- $2,068.00
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Independent 100-hand blocks and normal approximation; estimates are supplied, not inferred.
Poker variance and session standard deviation
Let N be hands divided by 100. With independent equal-variance blocks, expected profit is win rate × N and session standard deviation is deviation-per-100 × √N. At 5 bb/100 over 10000 hands, expected profit is 500 bb. With 80 bb/100 deviation, session standard deviation is 800 bb.
An approximate normal 95% interval is mean ± 1.96 standard deviations: −1068 to +2068 bb in this example. It is a model interval, not a guaranteed range or a confidence interval for a precisely known win rate.
Poker risk of ruin and bankroll assumptions
A win rate estimated from short results is uncertain. Dependence, changing stakes and skewed tournament prizes can violate this normal model. For a constant-drift infinite-horizon approximation, use the risk of ruin calculator with a consistent bankroll unit and variance.
Hand equity from the poker odds calculator does not itself provide a win rate or session variance. Enter independently justified estimates rather than deriving them from one showdown.