OUTS: ‘Three strikes, you’re out’ is a common baseball term. Three outs and an inning is over in a baseball game. In poker, an ‘out’ is used to refer to the remaining number of cards in the deck that will make or complete your hand. For example, let’s say that you have KsQs in your hand and the board is Ts-4s-Ad. You need another spade to hit a flush. How many spades are there left in the deck? Well, there are 13 of every suit, right? You have two spades in your hand with two of them on the board. So, of the known cards, (your pocket cards and the community cards) four of them are spades. That means that you can estimate that there are 9 additional spades remaining in the deck. Now, players could have folded their pocket spades, thereby making them unavailable for you to hit them on the turn card or river card, however we have now way of knowing that with certainty. So, we will keep it simple and estimate that there are 9 spades ‘somewhere’ in the deck. Knowing that there are nine spades left, those spades are what we refer to as our ‘outs’. Our opponent is betting and we are calling, hoping that we hit one of those remaining spades. We have now way of ascertaining what our opponent’s hand is of course, but through his actions we will put him on a hand, that is to say, we will mentally assume he has a specific hand. Based on what he has done, let’s say we deduce that he likely has at least an ace in his hand. So he has at least a pair-of-aces as his hand. We know that we are drawing and assume that we need to hit one of our spade outs to beat him (we have other ways to win, but for this example we will explore only hitting our flush). How many cards are in the deck in total? 52. And again, we know what 5 of them are after the flop. After the turn, we will know what 6 of them are (two in the pocket and the board four community cards). So, before the turn card, what are our chances of hitting a spade? Well, on the turn it would be 9 of the 46 unknowns. 9/46 is .1956. So our chances are 9 in 46, or roughly just under 20%. If we stuck around for the river card, we would have an additional shot of 9/45. It might get costly to call though as our opponent will bet to get rid of us and try to ‘take-it-down‘ right there. Unless you have ‘the nuts’ (the best possible hand) then you do not want to give opponents a chance to draw out on you. In this case, the opponent would not want us to hit one of those 9 spades. If he is a skilled player, he will recognize the possibilities and bet enough to insure that we never see the cards to come.
There is actually a simple way to calculate a reasonable approximation of your odds of making that flush, or whatever hand the case may be. It is called ‘the rule of 2 and 4’ (explained under separate FAQ title).