Winning chance as a %

Whats the formula for calculating your outs as a percentage chance of wining the pot?

I calculate pot odds as a ratio but isn't there a formula like #outs+x(y) to give you your chance of winning the hand as a %?

Cheers

BTW I'm hoping this is going to be my only dumb-dumb question

Outs * 2 if there is 1 card left to come.
Outs * 4 if there is 2 cards left to come.

Generally you use the * 2 method unless you are calling an allin on the flop, as you may face another bet on the turn, so you may not get to see both cards for the price you are being offered.

That will give you the percentage your hand will hit it's outs. But not the percentage your hand will always win. Since we don't know our opponents exact hand, there will be times when our out comes but we still lose.

To convert the % back to a ratio, divide the percentage into 100 and subtract 1 from your answer. That is if you have a 20% chance of hitting your hand, it's 100/20 = 5... 5 - 1 = 4.... So you have a 4:1 chance of hitting.

Hope that helps.

Thanks Stacks but...

That doesnt seem right. Arent you supposed to add something before multiplying # of outs by 2?

Using your method, if we have 9 outs it gives us an 18% chance of hitting one on the turn. However, 9/47(100/1)=19.14%

Its a small difference sure, but if were allin on the flop that diff is doubled. In some cases the difference is nearly 3%. Believe me Im not picking holes. I just thought there was a number to add before multiplying by 2.

Originally Posted by OhBollocks

Thanks Stacks but...

That doesnt seem right. Arent you supposed to add something before multiplying # of outs by 2?

Using your method, if we have 9 outs it gives us an 18% chance of hitting one on the turn. However, 9/47(100/1)=19.14%

Its a small difference sure, but if were allin on the flop that diff is doubled. In some cases the difference is nearly 3%. Believe me Im not picking holes. I just thought there was a number to add before multiplying by 2.

Stacks (and most poker pros, from what they write) use the Rules of 2 and 4. UNDERESTIMATING your probability of winning a hand is good - a little built in margin of error.

BTW, it's often hard to know which of your outs are actually live. Playing it conservative with just x2 (one card to come) and x4 (two cards to come) is fine - we generally can't get any more accurate than that with our estimates anyway.

Thats a fair point and the reasoning for underestimating is a sound one of course.

Cheers

At the table in the heat of the moment, a rough estimate is good enough.

1% or there about will never be the determining factor of calling a bet or not. The 2 and 4 rule is standard. What most people fail to learn is that the 4 is only good if you plan on seeing both streets for the same price.

Yeah, as for the "adding something" bit: outs x 2 + 1.

Eg: 9 outs == 9 x 2 + 1 = 19%.

Originally Posted by jyms

1% or there about will never be the determining factor of calling a bet or not. The 2 and 4 rule is standard. What most people fail to learn is that the 4 is only good if you plan on seeing both streets for the same price.

Also remember you often have "outs to outs." Example: Hero holds TT on a 983 flop. Even if Hero is worried about an over pair, he has 8 outs to an OESD (16% chance) after the turn. This is NOT the case with a 986 flop where Hero's set might make Villain's straight.

It's important to put villain on some kind of range when doing this, but Hero should think about which cards left in the deck are "good" and "bad" and which are "blanks" (no likely help to either Hero or Villain). Often a mediocre hand that is likely behind on the flop will have enough "good" cards left in the deck to make continuing worthwhile. Depends on villain, action, stack sizes, reads and other things, of course. But it's often correct to "get out ahead" of a hand when Hero has lots of good cards (12+) that will make a strong draw on top of the current holding. Fold equity plus the outs often make aggression the proper play.

When thinking this way, use the x2 rule to determine probabilities, reads to determine fold equity, and good judgment to decide how to play it.