Win rate calculator

How long until you know you're a winner?

Your results are part skill and part luck. Put in how much you win and how much you swing, and see how much of your win rate is real — and how long the luck takes to wash out.

Until you'd know you're a winner 750 hours if your results run at exactly +5 bb/hr — about 17 months at 10 hours a week

Half the time results run worse than your true rate, so that's a coin flip. For an 80% chance your results prove you're a winner, allow about 1,500 hours.

Too soon to tell

After 200 hours at +5 bb/hr, your true win rate is 95% likely to be somewhere from −4.7 to +14.7 bb/hr. The range still includes losing, so your results can't yet tell skill from luck.

What a true +5 bb/hr player sees
After	Chance of being down	95% of results land between
10 hours	41.1%	−38.4 and +48.4 bb/hr
50 hours	30.7%	−14.4 and +24.4 bb/hr
100 hours	23.8%	−8.7 and +18.7 bb/hr
250 hours	12.9%	−3.7 and +13.7 bb/hr
500 hours	5.5%	−1.1 and +11.1 bb/hr
1,000 hours	1.2%	+0.7 and +9.3 bb/hr
2,500 hours	under 0.1%	+2.3 and +7.7 bb/hr

Why your win rate isn't your win rate yet

Poker swings are huge next to the edge that wins. A live player who wins 5 big blinds an hour can easily be 70 big blinds up or down in any single hour, so a few hundred hours of results are still mostly luck.

The luck shrinks with the square root of the time you play: four times the hours only halves it. That's why the range above narrows so slowly.

95% range = win rate ± 1.96 × swing ÷ √hours

Online, count in hundreds of hands instead of hours: after 50,000 hands, divide by √500.

How many hours — or hands — you need

Turn the formula around to find when that range stops including zero:

hours to know = (1.96 × swing ÷ win rate)²

At 5 bb an hour with a 70 bb swing, that's about 750 hours. Halve the win rate and it takes four times as long: about 3,000 hours. Online, at 4 bb/100 with a swing of 90, it's about 190,000 hands.

That assumes your results run at exactly your true rate. Half the time they run worse, so for an 80% chance of your results proving it, allow about twice as long.

What's your swing?

Your swing is the standard deviation of your results: how far a typical hour, or hundred hands, lands from your average. More all-ins and bigger pots mean a bigger swing.

Online 6-max no-limit hold'em usually runs about 80 to 100 big blinds per 100 hands. Live no-limit varies far more, with how many hands you see and how you play: very roughly 40 to 100 big blinds an hour. If you track your sessions, PotCheck's tracker works yours out from your own results — no hand histories needed.

What this can't know

It treats every hour as the same: same game, same stakes, same you. Real results drift — you get better, games change, tilt happens — so a real win rate is less certain than this, not more.

Knowing you're a winner is half of it. The other half is not going broke on the way: the risk of ruin calculator works out the bankroll for your win rate and swing.

Session tracker

Get these numbers from your own results

Log your sessions — balance before and after, when you sat down and stood up — and PotCheck works out your real hourly, your swing, the range your win rate is really in, and your risk of ruin. Free, no ads.

Start tracking, free → See an example