It's very difficult to calculate the exact odds of hitting a draw when you're sitting at a table. Unless you're a math genius like Chris Ferguson, you won't be able to do this math. Which leaves us with two options: The first is to sit at home with a calculator and combine all the odds for all possible draw combinations, then memorize them. That way, no matter the situation, you'll always know the odds. But for those without perfect memory, there's an easier way: Here's a simple trick to estimate the odds:
The first thing you need to do is figure out how many 'outs' you have. An 'out' is any card that gives you a made hand. To do this, simply count the number of possible cards that complete your draw. For example: suppose you hold an A of clubs and an 8 of clubs and the flop comes a Q of hearts, a 9 of clubs and a 4 of clubs. You have a 'flush draw'. There are thirteen clubs in the deck and you are looking at four of them - the two in your hand and the two on the flop - which leaves 9 clubs in the deck and two chances to hit one.
The trick to calculating the approximate percentage of hitting a flush is to multiply the outs times the number of chances to hit it. In this case, that would be nine outs times two chances, or eighteen. So take that number and multiply it times two. The approximate percentage of the time you will hit a flush is 36% (the exact percentage is 34.97%). Now let's say that on the same flop you hold the J of diamonds and the T of hearts. In that case, you would have an OESD with eight outs to hit the straight (four kings and four eights). Eight outs with two cards gives us 16 outs. Multiply that times two and you will hit the straight 32% (31.46% exactly) of the time.
One important thing to keep in mind is that the percentage shown is merely the percentage of the time you will make your hand, NOT the percentage of the time you will win the pot. You can make your hand and still lose. In the first example, the Q of clubs would make a pair on the board and give you a chance of a full house. In the second example, either the K of clubs or the 8 of clubs would put a possible flush on the board, giving you the straight, but not necessarily the winning hand. Knowing the approximate probability of making your hand is a good first step to becoming a good poker player.
Original from March 21, 2005, Author: Team Full Tilt – Full Tilt Poker – link (authorized reproduction)
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Hey buddy!
Your article is interesting. However, like all the others I found on the subject, the only odds mentioned are for flush or straight draw, without going into much detail. I would like to know the mathematical possibilities for all types of games and in all types of situations (I believe it is possible), pre-flop, flop, turn, river, against 1, 2, 3, …9 opponents, flush, straight, full house, in short, everything; and I don't feel like memorizing anything at home hehehe. Another thing is the software that does this type of calculation. Do you know any? Do you use them? Do you recommend them?
A hug!
Gabriel, the article is indeed introductory.
There are several programs that do this, I suggest asking on the poker tips forum to find out which ones are most used.
The odds do not vary depending on the number of opponents. The calculation becomes quite easy after a little practice.
For example: You have :Ah :Ks
Flop :Jh :Th :7c
Depending on the reading you can consider that you have 11 outs in this situation to form one of the following: High Pair, Straight, or running-running flush.
You can use the 4×2 rule in any situation by multiplying the number of outs by 4 after the flop and by 2 after the turn. Always keep in mind that the odds do not guarantee a win even when you hit a killer hand.
Imagine you have two over cards and a flush draw after the flop, in which case you would have 15 outs to beat a possible top pair from your opponent – 6 outs to pair one of your two cards and +9 for the flush. So you would then have approximately a 60% chance of making a winning hand.
Exactly, good summary on the subject.