Poker Variance & Confidence Calculator
Calculate expected variance, confidence intervals, and sample size needed to prove your win rate
About this calculator
The Poker Variance & Confidence Calculator helps poker players understand the statistical significance of their win rates and expected swings. Variance is inherent in poker due to luck factors, making it difficult to determine if short-term results reflect true skill. This calculator computes confidence intervals around your win rate, shows expected variance ranges, and determines how many hands you need to play to statistically prove your edge with mathematical certainty.
How to use
Enter your win rate (bb/100 hands), standard deviation, and desired confidence level (typically 95%). The calculator will show your expected variance range and confidence intervals. To determine sample size needed, input your suspected true win rate and the minimum edge you want to prove statistically.
Frequently asked questions
What is poker variance and why does it matter?
Variance measures the natural swings in poker results due to luck. Understanding variance helps distinguish between skill-based winnings and temporary hot streaks or downswings.
How many hands do I need to prove my win rate?
This depends on your win rate and desired confidence level. Generally, you need tens of thousands of hands to prove a small edge statistically.
What confidence level should I use for poker analysis?
95% confidence is standard for poker analysis, meaning you can be 95% certain your true win rate falls within the calculated interval.