On the turn pot odds to call versus outs

Question

When facing a bet on the turn (river card to come) how to equate call a bet to number of outs?

You think you are beat but you have a number of outs.
When is it profitable to call?

Answer 1

Whether or not it is profitable to call depends not only on # of outs but on the format of the game (i.e. ICM may be the biggest consideration in MTT/SnG)

A really simple rule I was taught to calculate equity is:

# of outs after flop * 4 ~ equity

E.g. You are 4 to a flush on the flop. Without knowing any other cards, you have 13-4 = 9 outs. Then 9*4 = 36%, which is roughly correct. The exact answer accounts for the normal distribution of your suit amongst opponent cards

Answer 2

A quick approximation method is the following:

A) Equity from flop to river = Number of outs x 4 %

B) Equity from flop to turn = Number of outs x 2 %

C) Equity from turn to river same as B)

Example: Flush draw from flop to river has ~ 9 outs x 4% =36% equity. From turn to river it is ~ 9 outs x 2% = 18%

Of course this method will only calculate the immediate pot odds (equity). The are many other factors to decide whether it is a good decision to call or not (such as implied odds, table image, ability to bluff your opponent, tournament life etc.)

Answer 3

If ur not getting the right odds to call figure out how much more would have to be in the pot for it to be right then decide if u can get ur opponent to call that amount or more if u hit. That is implied odds.

Answer 4

I ran the numbers recently and thought it might be of value to others

On the turn with one card to come there are 52-6 = 46 cards left

The math on call is

(bet + pot) / bet = (46 - outs) / outs

The way I remember it is my bet and my outs are on the bottom (denominator)

1 + pot/bet = (46 - outs) / outs
pot/bet = (46 - outs) / outs - 1
pot/bet = (46 - 2*outs) / outs
bet/pot = outs / (46 - 2*outs)
that might be a too much to run in your head at the table
calcs below

outs  bet/pot   
1     0.0227
2     0.0476
3     0.0750
4     0.1053
5     0.1389
6     0.1765
7     0.2188
8     0.2667
9     0.3214
10    0.3846
11    0.4583
12    0.5455
13    0.6500
14    0.7778
15    0.9375
16    1.1429
17    1.4167
18    1.8000
19    2.3750
20    3.3333
21    5.2500
22    11.0000
23    ∞  

At 23 outs you cannot be priced out. You are 1:1 to win.

Just memorize a few
A bet of 1/3 the size of the pot you need 9 outs
A bet of 1/2 the size of the pot you need 12 outs
A bet the full size of the pot you need 16 outs

A flush, open ended straight draw, with 2 overs is 21 outs
Are all those outs good is another thing

That is just immediate pot odds. If you think you can get more money on the river if you hit then the implied odds are better.