The Importance of Stack Size

Understanding both when and how to use your stack sizes to your advantage in a tournament is one of the most underrated and misunderstood skills in poker. So many players think you just loosen up with a big stack and bully the table, or that when you are short stacked you either need to wait for a hand, or start pushing like crazy to build a stack back up. There is so much more to it.

We'll discuss some specific moves, and when to use them, a little later. For now we need to outline the basic skills involved, and what you should be thinking about. Using your stack to it's full potential requires a number of factors, and some experience, but working on the skills below will help you to get there quickly.

In order to make use of the other skills, you must first work on your ability to plan ahead and pay attention. Watch your opponents and how they deal with short or large stacks, whether they like to get all-in, or are terrified of it, and how desperate they might be. You really want to know how much this player wants to gamble with the stack he has, and it will be paramount to your decisions regarding stack size.

If you can find a player who hates to gamble, there are constant opportunities to abuse him. Likewise a player who isn't afraid to get his chips in the middle and loves to reraise or to make squeeze plays, can be punished for his tendencies. You can see how this works with a quick example -

You are playing a 6-max sit and go tournament, and there are four of you left. The blinds have started to be uncomfortably high (300-600) and you are in third place with 2,200 chips. You are on the button and the player to your right folds. Now you have the small blind with only 1,100 chips who has been tight and timid, as well as the big blind who has 3,200 in his stack and who has been a fairly solid player, gambling when necessary but not wild.

When you look down at the 7-5 of spades, what is your move?

For many reasons, this is an easy push all-in for an experienced player. The blinds are big and you really need them, but your knowledge of your opponent's stack sizes and playing tendencies are the reason you can make this play. The small blind will only call with a real hand, and if he calls you are getting a good price with a hand that plays fairly well all-in.

The big blind won't call without an absolute monster, because you have enough chips to really hurt him, and he's headed toward the money. He has no desire to end up with 1,000 chips and your pushing all-in has threatened him with that very thing. Both of your opponents are afraid of elimination, so they are going to be tight here to an all-in raise, and those blinds are going to be a big help to you.

Planning ahead is also very important, and we can see that clearly if we take our previous example and make the blinds 50 and 100. Now you can raise to 300 or 400, but are you going to fold to a reraise from the small blind when you are getting such a good price? And isn't he going to assume that you may be on a steal because of your button raise? You don't want to play your 7-5 suited for 1,100 chips when the blinds are only 50-100. And if the big blind reraises he will force you to be committed to the pot. You don't want to be committed to the pot over such small blinds, so here you just fold your button unless you really are certain that you can steal the blinds without a fight.

You must remember to plan ahead to keep yourself out of trouble, while either scaring your opponents with the threat of trouble, or when you really want action, sucking them in to playing a big pot with you when they shouldn't be.

One of the best tools for learning about short stack play is called an ICM calculator. These wonderful tools are mostly used by sit and go players, but more and more multi-table tournament players are learning how useful they can be. ICM stands for Independent Chip Modeling, but that's not important. What is important is that an ICM can actually take certain poker situations and break them down to mathematically correct plays.

It's a rare thing in poker to be able to know with certainty what the correct play is, but as the blinds get higher compared to your stack size, the ICM can do just that. An ICM calculator by itself can be cumbersome and tough to really understand, so many automated ICM calculators have appeared. Sit and Go Power Tools, SitnGo Wizard, and Sit and Go End Game Tools (SNGEGT) are the front runners in this market. You just tell the program your hand, the blinds, and your opponent's stack sizes, and they do the rest, giving you perfect advice in short stack situations.

Working with an automated ICM can not only show you the correct plays, but it will teach you to make them and understand them. It will teach you the value of fold equity (the chance that your opponents may fold to your bet and give you the blinds) and it almost universally makes its users more aggressive when the blinds get high.

Playing a big stack is more of an art than a science, and most players are really terrible at it. Watching an online tournament from the beginning will usually have you wondering where those early big stacks went as the tournament goes on, because the players who got them didn't have any idea how to keep them.

Aggression is important with a big stack, but you must choose the targets for your aggression carefully. Most players play far too many hands once they get a big stack, and end up handing away a big chunk of it before they slow down. It's best to simply use small bets with the force of your huge stack behind them, and then get out of the way if someone comes over the top with a big reraise. Would they be fighting with the biggest stack at the table if they were dealt rags? Probably not. You can be sure that they're looking at that stack and salivating over the upcoming double-up. Don't give it to them.

If you think ahead, pay attention to your opponents and how they might be thinking, and watch the way you play with a big stack, you can dominate a table from below or above, and your stack size won't bother you any more. In fact it will become your favorite weapon.