Pot commitment is one of the most difficult concepts for a poker beginner to understand. The concept is simple, but its application is complicated. This is especially true when we must determine whether we are committed when our hand is a not-yet-made drawing hand.
What is pot commitment?
The term “pot committed” simply means that you are in a spot in which no matter how much your opponent bets or raises, your correct response is to call or raise up to and including all-in. I talk about this concept in my book Poker Beginner to Poker Winner in 1,000 Hands: Keep Calm and Re-Buy, Volume I. Available in paperback or Kindle on Amazon.
Also available here as a .pdf.
The chapter on pot commitment follows the chapter on stack to pot ratio which is one of the key factors in determining pot commitment, which is one of the key factors in earning money playing poker. Stack to pot ratio, also called SPR, is the number you get on the flop by dividing the size of your stack by the size of the pot. For example, if the pot is seven big blinds as the flop is dealt, and you have seventy big blinds left in your stack, the SPR is 10:1 or you could just say the SPR is 10. If you had only twenty-one big blinds left in your stack as will often be the case while short-stacking, your SPR on the flop is now 3:1 or simply 3.
Do not fall asleep!
If this sounds too mathy and you are about to zone out, don’t. Stack to pot ratio is the key poker concepts to understand post-flop with any more than forty-five or so big blinds. In countries like Japan, they teach kids the number line from day one because is is so important to all other math. If I was teaching no limit hold ’em poker school the first thing we would learn is SPR.
With the default and adjusted short-stack strategies, our stack size nearly guarantees us a small SPR on the flop which is where our top pair and over-pair hands perform best. So when following The Plan, we don’t think much SPR, except maybe in a limped pot. If you want to moved the the next phase, The Plan Part Deux, which is moving to live play or to full stacked online, you must understand SPR. It will be covered extensively in Volume II.
How SPR Underpins Pot Commitment
Stack to pot ratio is the foundation of pot commitment. However, it is not the only part of pot commitment. You nearly always have to take into account the psychology of your opponent to know if you are pot committed.
It is not enough that you believe that your hand is currently better than your opponent’s hand. You must also estimate that Villain will call with more of his range that you are beating than with the part of his range that beats you. If you have ace-queen on a queen high flop, you know villain will call with a set of queens, or a set of the other two flop cards.
If you are considering pot commitment when calling a bet, you would estimate the range of hands that Villain would bet up to all-in with and your odds against beating that range with your hand.
When you are definitely committed
With a drawing hand, you are definitely committed when the size of the pot and the size of the smallest stack in the pot offers payoff odds better than your odds against filling your hand. For example, if you have a flush draw on the flop and your stack is less than the pot, you are committed. No psychology needed, or maybe it is better to say the psychology is built into the math. Here’s the math:
Your flush draw has about a 35% probability of filling for odds against winning of approximately 1.86:1 because 65 / 35 = 1.85714. A pot size by either player offers odds of exactly 2:1 if called. You will not fill your flush more often than you will fill it, but this would still be a good bet or call. That is because in the long run, you will make more money by calling than you will lose.
Of course that is all based on the assumption that filling your flush means winning the hand. I believe that is a valid assumption because you will win the overwhelming majority of times with a flush. The few times you lose to a bigger flush or a full house or better will be offset by those few times you do not make your flush but still win the hand due to having the high card or making a pair plus on the turn or river.
Suppose your draw is to a straight and not a flush. With an open-ended straight draw, your probability of filling is approximately 32%. Odds against winning are 2.13:1 because 68 / 21 = 2.125. That is slightly worse than 2:1. But if you happen to have even a little less than a pot-sized bet, you are mathematically committed. an 85% pot all-in gives you payoff odds of 2.17:1, slightly better than your odds against winning.
When you might be committed
But suppose you have a pot sized bet left exactly with a straight draw or a little more than a pot sized bet with either draw. You might be committed based on your cards and your reads on the villain in the hand with you (reads, not guesses). If you have a suited ace-king and flop a flush draw, your hand will flop ace-high with one over-card at worst. Might this Villain call a shove that is a little more than the pot with ace-weaker or king queen overcards? If so, you are committed. Would this villain call with a worse flush draw? You are committed.
If you have significantly more than the pot in your stack and villain does also, you are not committed unless you have specific reads on this villain. Is he a loose-passive fish that cannot fold even a non-paired hand that you are beating with your AK? Will he keep putting money in the pot if the third of your suit turns or rivers and you know he does not have the ace or king of it? Either way, you are committed due to the implied odds this spot offers.
Fold equity and pot commitment
I would argue that fold equity is part of pot commitment when you have the initiative. You see this concept in play with the default short-stack strategy which calls for you to aggressively bet the flop with a strong draw to include betting all in, even for greater than the pot. With 30BB, your maximum SPR following the default strategy would be 2.88. Maximum. With that SPR, you are likely to be called by top pair type hands that your draw will beat if it fills. But you are also likely to get folds from second pair, middle pair, third or bottom pair, better hands than you have now. You may get folds from a stronger draw.
I would say that they above is true for NL10, but not NL5 or below. I tried the default at NL5 and it did not work because it did not get enough folds. It sounds absurd but the NL5 players often win against the default strategy because they are not good enough to fold. A default NL5 strategy would need to be as tight as the original 20BB strategy, if not tighter.
One problem that beginners consistently have is that they start by calling too much and then when they learn to be tight-aggressive, they fold to much. Understanding commitment with drawing hands will help you overcome that. Remember, each stack is to be risked to grow your earnings. When you lose a stack because your draw does not fill, just keep calm and re-buy!