Explain Poker Like I’m Five: ICM

When you’ve played poker for years, it’s easy to forget that technical poker speak may as well be a different language. Many players just picked up a deck of cards for the first time and are wondering what the hell a reverse implied range merge against a large stack to pot ratio is.

Maybe you are new to poker as well and want to start analyzing the game at a deeper level, but the lingo and foreign concepts get in the way. To help, Card Player brings you this brand new series, Explain Poker Like I’m Five.

Every issue, we’ll take on a new term or idea, perhaps one you might come across elsewhere in this very magazine, and we’ll break it down to its simplest components.

The Concept: ICM

What Is It?

ICM, also known as the Independent Chip Model, is a mathematical formula used by poker players to calculate the equity of their chip stack in a tournament. Players often use these calculations to make better decisions in subsequent hands or even to determine a fair and equitable deal when chopping up remaining prize money. Tournament chips hold a non-linear value, meaning one big blind is worth more to a short stack than one big blind for the chip leader.

Okay, Now Explain It Like I’m Five

ICM is math that tells you how much your tournament chips are worth in real dollars.

Give Me An Example

Imagine a $10 sit-and-go with nine total players, creating a total prize pool of $90. The first place prize is $45. The second place prize is $30 and the third place prize is $15.

Each player started with 1,500 in chips, putting 13,500 chips in play. After an hour of action, there are just four players remaining with the following stack sizes and blinds of 100-200:

Joe – 6,200
Mary – 3,900
Erik – 2,600
Wendy – 800

After inputting the above numbers into an ICM calculator, we can learn a lot about correct strategy for playing on the bubble. For example, Joe might be less inclined to call an all-in from Mary without a big hand in order to protect his sizable chip lead. Erik, on the other hand, would be making a big ICM mistake if he called all in with a marginal hand, since Wendy is down to her last four big blinds.

If the four players agreed to an ICM prize pool chop, the payouts would be as follows:

Joe – $33.06
Mary – $27.24
Erik – $21.90
Wendy – $7.80

As you can see, Joe’s big chip lead means his current stack is worth just over second-place money. Despite being extremely short-stacked, Wendy’s chips still hold significant value.

This calculation is different than a chip chop, which would theoretically award Joe $41.40, which is 46 percent of the remaining prize pool. Wendy, holding just six percent of the chips in play, would be awarded just $5.40.

This contrast is why many poker players prefer to make deals using ICM, while simultaneously adjusting for the differences in skill level between the remaining players. ♠