Poker Variance Calculator
Poker variance explains why a winning player can lose for months straight and why a losing player can feel like a genius for weeks. Our poker variance calculator uses a Monte Carlo simulation to show how extreme your results can be with any sample size. This allows you to plan your bankroll, manage your expectations, and distinguish between bad luck and poor play.
Simulation Parameters
Enter your poker statistics to run the variance simulation
How to Use This Calculator
The calculator needs four inputs. Here is what each one means and how to set it correctly.
- 1Win Rate (BB/100): Your bb/100 from PokerTracker 4 or Hold'em Manager. A solid NL Hold'em 6-max regular wins 2 to 6 bb/100 after rake. If you don't know yours yet, use 2.5 bb/100.
- 2Standard Deviation (BB/100): How much your results swing around your average. Find it in your tracking software under 'Std Dev' or use the reference table below. For NL Hold'em 6-max, 80 to 100 bb/100 is typical.
- 3Sample Size: The number of hands to simulate. Common choices: 50,000 (1 to 2 months part-time), 100,000 (standard evaluation window), 500,000 (full year of volume), or 1,000,000 (career perspective).
- 4Observed Win Rate (Optional): If you have already played a sample, enter your actual win rate here. The calculator computes the probability of running at or below that rate, which answers: 'Am I running bad, or is my win rate lower than I think?'
Reading Your Results
The simulator returns five key outputs. Expected winnings is your average profit at the given win rate and sample size. The 70% and 95% confidence intervals show the realistic range: a 3 bb/100 winner over 100,000 hands has a 95% range spanning roughly 30 buy-ins in either direction.
Probability of loss is the chance you finish in the red despite being a winner. For a 2 bb/100 player with 90 bb/100 SD, that probability sits around 18 to 20% after just 50,000 hands.
Maximum drawdown is the deepest peak-to-trough decline you can expect and sets your minimum bankroll. Downswing frequency tracks how often dips of various depths occur: a 15-buyin downswing happens multiple times per 100,000 hands, while a 30-buyin downswing is uncommon but far from impossible.
Standard Deviation by Poker Game Type
If you don’t know your SD, use the typical range for your format from the table below. These are compiled from large sample databases and industry-standard poker tracking tools.
| Game Format | Typical SD (BB/100) | Notes |
|---|---|---|
| NLH Full Ring (9-max) | 60 – 80 | Tighter play, fewer large pots |
| NLH 6-max | 75 – 120 | Most common online format; LAG styles push SD higher |
| NLH Heads-Up | 100 – 140 | Highest NLHE variance due to constant blind battles |
| PLO Full Ring | 100 – 140 | Closer equities increase swing potential |
| PLO 6-max | 120 – 160 | High multi-way action; aggressive styles can exceed 170 |
| PLO Heads-Up | 140 – 180+ | Extreme variance; bankroll requirements are massive |
How to find your SD in tracking software: In PokerTracker 4, go to “More Filters” > “Statistics” > “Std Dev BB/100.” In Hold’em Manager, it’s under “Reports” > “Session” > “Std Deviation.” If you’ve played at least 20,000 hands, use your actual number for the most accurate simulation.
Related Tools & Guides
Once you’ve run your simulation, use these resources to take action on the results.
- Read our full variance in poker guide for deep coverage of risk of ruin, PLO variance, the Kelly Criterion, tilt management, and more.
- Use our poker bankroll calculator for personalized stake and bankroll recommendations based on your win rate.
- Run tournament simulations with our MTT variance calculator, designed for field size, ROI, and payout structure inputs.
- Browse the full poker strategy hub for preflop charts, post-flop concepts, and format-specific guides.
- Compare our best rakeback deals to find the lowest effective rake and reduce your variance exposure.
Frequently Asked Questions About Poker Variance
What is a good standard deviation in poker?
Standard deviation isn’t inherently “good” or “bad.” Rather, it reflects your playing style and game format. For NLH 6-max, 75-100 BB/100 is typical. A standard deviation below 75 suggests a tight-passive style, while a standard deviation above 100 suggests a loose-aggressive approach with frequent 3-betting and large pots. Due to closer equity matchups, PLO standard deviations run 120-160 bb/100. A lower standard deviation (SD) means you need a smaller bankroll for the same win rate. However, it doesn’t inherently mean you’re playing better. Many winning players have high SDs because they aggressively invest when they have an edge.
How many hands do I need to know my true win rate?
The number of hands needed for a rough estimate in NLH depends on your standard deviation. A minimum of 100,000 hands is needed, and even then, your 95% confidence interval spans about +/- 1.6 bb/100. To reach a practically useful confidence level of +/- 0.7 bb/100, you need around 500,000 hands. PLO players need roughly double these numbers due to higher standard deviations. The formula is: Margin of Error = 1.96 x SD / sqrt(hands / 100). You can plug your numbers into our poker variance calculator to see your personal confidence intervals.
Can a winning player go on a 100,000-hand downswing?
Yes, and it’s more common than most players realize. A player with a 2 BB/100 winner and a 90 BB/100 SD has a 10-12% chance of ending up in the red after 100,000 hands. That’s about 1 in 9. Deeper downswings of 30-40 buy-ins that persist across 50,000-100,000 hands occur in about 5-10% of simulations for marginal winners. This is why professional players, staking groups, and coaches emphasize that playing a large number of hands reduces the impact of variance and that sample sizes below 100,000 hands reveal little about true ability.