Pot odds and open-ended straight draws



Ok, i just went on a little 6 mile run to clear my head and i happened to be thinking about -- you guessed it -- pot odds and open ended straights. This will be of little use to advanced players but for the intermediate player who is just beginning to play pot odds, it may be the difference between a winning and losing play over time.

basically, on an open ended straight off the flop you have 8 outs twice, for a total of 16 and about a 34% chance to hit it by the river. that means if the pot is paying better than 2 to 1 you have the odds for a call, right? (you have to win 1 in 3 to break even) Not necessarily, and here are two possible reasons why.

If there are two suited cards on the board, and you put your opponent on a flush draw, then two of your outs will give you a straight but they will give him the winning flush, and probably cause you to go broke in the process. that means that if there are two suited cards you may only have 6 outs twice, for a total of 12 and about a 26% chance to win the hand. your opponent on the other hand has 9 outs twice, for a total of 18 and close to a 39% chance to hit it. that means while he only needs 2 to 1 odds to justify a call, you need 3 to 1 odds to make money on the play. This is a bad situation to be in if you intend to make $$ over time.

another possible reason you could go broke is if the board pairs. you need to be *especially* cautious if the board pairs connecting cards, because people are much more likely to play connectors like 9 10, or 10 J. so if the board comes 10 J J, and you have Q K, you need to be careful because your opponent may have just flopped the boat. in any case you have to bet at this, if you are first to act you should throw about 1/3 to 1/2 the pot at it. if you get raised you should seriously consider dropping the hand. you might try a small reraise to define the hand, because 90% of players online can't resist going all in after a you bet, they raise, you reraise. if you are going to stay with the hand i'd advise the raise here instead of just a call. if you just call, you haven't learned anything about his hand and you are wandering down 4th street blind.
if you are last to act and he leads into you with a bet, you need to raise him. most players will go all in with the boat after that, although a smart player will just call to get another bet on 4th street.

Now, even if he hasn't gotten the boat yet, lets say he hits his trips on the flop. lets say he's playing J 9s (a possible starting hand if he's got position), and the board is 10 J J. you still have K Q. So you have 8 outs twice, and a 34% chance to hit the straight. the problem is that your opponent also has a decent number of outs. he has 3 9s, 3 10s, and 1 J on the turn to give him a boat or 4 of a kind, for a total of 7. in addition, his 9 will give you the straight and him the boat, causing you to go broke... so it is really tied 7 to 7 on the turn. then if he doesn't pair on the turn, he actually picks up another three outs for the river card. Say the turn comes and its a 2, a harmless card. that means he now has 3 9's, 3 10's, 3 2's and 1 J that will win, and you are still stuck with 8 outs (perhaps only 7, if you put him on the J 9). What does that mean? to call on the river with your 8 outs you need better than 4 to 1 pot odds, but he only needs 3.5 to 1. plus, if the 9 lands his implied odds are enormous... you need to be very very careful when the board pairs.

the moral of the story: if you are figuring your pot odds, do not count outs that are actually outs for your opponent!! if you do, you might go broke!


Rock Star
This is definitely a good tip for new/intermediate players. You definitely need to be aware of what outs are "dead" for your hand. If there's a straight-draw and a flush-draw on the flop, and you've got the straight draw.. yes two of your outs are covered by the flush-draw. However, I would caution that the flush draw may not be out there that hand, so.. sometimes the straight will hold up. I would not immediately bow out of the hand if you hit your straight and the board goes 3 to a suit. Early position is a good spot to be in here.. lead out with a bet and see what happens. If you're re-raised, the flush probably hit.. get out. If it's a call your'e gonna have to throw out another bet on the river.. same thing, re-raise was probably a slow-played flush.


9X4 36%.. (+1 if you want).. 4 and 2 method is about as easy as it is going to get.


The biggest problem IMO that intermediates have is basically what you just stated albeit long windedly, in your post: In correct out/odd calculation.

Most people who have [ks][Js] and see a flop [Qh][10c][5h] look and say to themselves "open ended straight 8 outs, 34% to make by the river, i need 2:1 pot odds to call. They may even have in the back of their minds that there is a flush draw out, but more often than not they don't equate that 2 of their 8 outs are dead. And In my opinion, the reason behind this is the thought proccess of OES/Flush draw outs.

A better way of thinking about it is just simply ESTIMATING outs. For example on the previous board, you've got "8" outs but in reality 2 of them MIGHT be dead, so 6 real outs and 2 semi-outs...which we can estimate as half an out. so, you have 6.5 outs to make your hand, or 13.8% chance on the turn and 14.1% on the turn...roughly 28% to make, or 3:1 pot odds to call with a flush draw on the board.

Keep in mind that you could still make your hand and lose the pot if you make your hand on the turn and the river completes the flush, or pairs the board giving a full to someone. But thats out of your control, you can only control the money in the pot.

The second biggest mistake is slowing down when one of the safe outs hits. Lets say in the above example the [As] falls. Too many people give too much credit to their opponents reading abilities. They assume they know that they hit their hands, and as a result, try and disguise it by playing slow! This is WRONG. You now have to protect your hand. Put in a big bet and make the flush draw pay 2:1 instead of the 4:1 needed. Sure you will lose once every 5 times, but the net profit is good. Don't allow yourself to think "I'd have saved money by checking" because in the same situation over time, you're going to MAKE money with a bet. Its +ev
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