Determine Stack Sizes and Odds

The Real Deal...

One of the most important factors in a No-limit Texas hold'em game is the amount of chips people have at the table. A person's stack size affects the strategy at the table in numerous ways. For example, the amount a person buys in for is often indicative of how well that person plays. Someone may buy in for a small amount because he is not very confident in his skills and does not want to risk much money.

However, the most important thing about stack sizes is how they affect implied odds. Implied odds is a fancy word for saying "how much you can expect to win in the future if you make a good hand, taking into account the chance of hitting that strong hand."

Say you hold 6 5 pre-flop. Your hand is obviously not that strong. It is also doubtful that you will hit a strong hand at the flop, like a straight or trips. However, you have a good chance of hitting a draw, such as a flush draw or a straight draw. To win a lot of money on this draw, you will probably need to call a bet on the flop and see the turn and river to get the card you need to make a strong hand. If you hit a strong hand, you will want to bet a lot when you have the strong hand.

If the stack sizes are small, you cannot expect to win much if you chase a flush or straight draw. Speculative hands like suited connectors do well when people have large stack sizes and perform poorly when people have small stack sizes.

To be precise, here is what I consider to be small, medium, and large stack sizes:

Small stacks 40 big blinds or fewer
Medium stacks 41 to 99 big blinds
Large stacks 100 big blinds or more

You will see different buy-ins for different types of games. For most home games, people buy in for small stacks. A home game with $.25-$.50 blinds will typically have $10 to $20 buy-ins (20 and 40 big blinds). These are small stacks.

The Real Deal casino games have variable stack sizes. Nowadays, it seems that most places in Vegas restrict the buy-ins to about 40 big blinds, so people tend to have short or medium stacks. However, there are brick and mortar games that do not cap the buy-ins, and people with 200 big blind stacks are common. The games at online poker rooms tend to restrict buy-ins to 100 big blinds, so many people have fairly large stacks.

Stack sizes do more than just increase the value of speculative hands. They also tend to make the game fancier. Bluffing becomes a more valuable tool when people have larger stacks. This is because you can threaten a much larger amount of money in relation to the pot when people have a lot of chips.

For example, suppose the flop is J 8 7. There is $10 in the pot. Your opponent has Q J. His top pair is a marginal hand. While it will beat most hands, there is a lot on the board that massacres his hand (straight, two pair, top pair with higher kicker, etc.)

Suppose you bet $10. If your opponent has a $10 stack, he will likely call you since he has so much already invested in the pot.

However, suppose your opponent has $100. He will be more wary of calling. If he calls and you fire another pot-sized bet on the turn, this means he will have to call $40 just to see the river. If you fire another pot or near-pot sized bet on the river, he stands to lose his entire stack due to this flimsy hand.

Large stacks tend to increase the value of bluffing, which also means marginal hands lose value. A hand like top pair will not get paid off when the stacks are large (except by draws or bluffs) because hands like middle pair are not going to pay off a large amount of money in relation to the pot.

Large stacks mean fewer hands go to a showdown, and the ones that do are much more likely to involve powerful hands like straights, flushes, and sets.