Another great article by Jeff Stanzel regarding probability in Poker. This is a great explanation on figuring out pot odds!

A popular way to decide if you should draw or not in Texas hold’em is to think of probability in an negative way. If you know the relationship between the odds of not making your hand and the money you will win if you hit your draw, you will be playing statistical poker, calculating pot odds and be on your way to becoming a long term winner.

Figuring out pot odds is easy. Follow the steps below:

1. Figure out number of unknown cards in deck

    52 - board cards - your hole cards = A

2. Decide on number of cards that will help make your hand  = B

3. A-B = number of cards that won’t help  = C

4. Odds against making your hand is C : B

Example:

You are on a nut heart flush draw with the river card to come.

1. Unknown cards are 52 - 4 -2 = 46. This is A.

2. Since there are four hearts known (two on board and two in your hand) and thirteen

    hearts in total, there are still nine cards that can help. So B = 9.

3. 46 - 9 = 37 = C

4. Odds against making your hand is 37:9 or 37 divided by 9 which is 4.11 to 1 ( 4.11 : 1 )

So, if the pot is at least 4.11 times your bet, then you should call, otherwise fold.

This is using probability in a positive sense to determine if you should draw or not. An easy way to approximate your percentage chance of making your draw is as follows:

Turn and River to Come:

1-9 Outs:     # outs x 4

10 -12 Outs  (# of outs x 4) - 2

13-15 Outs   (# of outs x 4) - 4

River to Come:

1-3 Outs:    # of outs x 2

4-8 Outs:  (# of outs x 2) + 1

9-15  Outs: (# of outs x 2) + 2

Example:

If you are on a nut flush heart draw with only the river to come you have 9 outs that will allow you to make your hand. Using the charts above, use the following formula:

9 x 2 + 2 = 20% which is real close to the actual 19.6%.

So in this case, you have a 20% chance of getting your flush. Ergo, the cost of your call should not be more than 20% of the pot’s total. In other words, you can call a bet up to 20% of the size of the pot since you win the pot about one in five times or 1 : 5.

Jeff Stanzel

www.justinbaxter.com