Tools / Poker Variance Calculator
Poker variance calculator for tournaments
Enter your ROI and field size and see how wild tournament results can be, even for a winning player. Free, no sign-up!
In short
A 20% ROI player in 500-player MTTs is still losing after 1,000 tournaments 12% of the time, and typically goes through a 93 buy-in downswing on the way. To keep the risk of going broke under 5%, they'd need about 218 buy-ins.
20 possible runs of 1,000 tournaments
Same skill, same ROI. Only the cards differ.
Grey lines: 20 sample runs. Green line: your expected profit. Shaded: where 70% and 95% of runs end up.
- Chance to be losing after 1,000
- 12%
- Even with a 20% ROI.
- Typical result (median)
- 185 buy-ins
- $3,691. 90% of runs land between -57 and 482 buy-ins.
- Typical worst downswing
- 93 buy-ins
- 1 run in 10 has a downswing of 156+ buy-ins.
- Longest stretch without a new high
- 406 MTTs
- 1 run in 10: 800+ tournaments.
- Bankroll for 5% risk of ruin
- 218 buy-ins
- $4,364. For 1% risk: 335 buy-ins.
- Cash rate
- 20.0%
- Standard deviation 5.4 buy-ins per tournament.
Downswings in these 2,000 simulated careers: 97% had one of 50+ buy-ins, 43% had one of 100+ buy-ins, 3% had one of 200+ buy-ins.
Why tournament variance is so big
Most of a tournament player's profit comes from a few deep runs. With 20% of tournaments cashed and most cashes small, a winning player can go hundreds of tournaments between big scores. That's why the 20 runs above look so different from each other, even though they're the same player.
What you can control
Variance decides the short run, but your ROI decides the long run. A lot of that ROI is won or lost with short stacks, where one wrong shove or fold costs real money every time it comes up. Tighten that up with the push/fold charts and practice the spots until they're automatic.
Common questions
- How big are normal MTT downswings?
- Bigger than most players expect. For a 20% ROI player in 500-player fields, the typical worst downswing over 1,000 tournaments is about 93 buy-ins, and 1 run in 10 sees 156 or more.
- How many tournaments do I need to know my ROI?
- Thousands. Tournament results swing so much that after 1,000 MTTs a winning player can easily show a loss, and a losing one a profit. Use the calculator with your own numbers to see how wide the spread is.
- How is the bankroll for 5% risk of ruin worked out?
- With the standard risk-of-ruin formula: bankroll = -variance × ln(risk) / (2 × win rate), using the per-tournament mean and standard deviation from the payout model. It assumes you never move up or down in stakes.
- What does the simulation assume?
- That you cash in every paid place equally more often than an average player, by just enough to give the ROI you enter, and that every tournament has the same field size and payouts. Real results vary more, since fields and structures change.
- Why are the graphs the same every time?
- The random numbers are seeded from your inputs, so the same inputs always draw the same 20 runs. That way a link you share shows exactly what you saw.
Sources and assumptions
- Risk of ruin (Wikipedia) - The chance of losing a whole bankroll, and the formula used here for a 5% and 1% risk.
The solved numbers on this page
- Finishes: you cash in each paid place equally more often than an average entrant, by enough to give your ROI.
- Payouts: a typical online structure for the share of the field paid, with a min-cash of about 1.2 buy-ins' worth of pool.
- Bands: normal approximation around expected profit. Risk of ruin: the standard formula, at fixed stakes.
- Seeded random numbers: the same inputs always draw the same runs.