Poker Odds Formulae

[stallyon]

Hi,

Not sure if this is the right place to post.

I'm looking for some formulae, calculations on how to determine odds for poker hands (prety much in the same way that PokerStove does)

Can anyone help?

Thanks

Nic

[the bus]

I think it just runs through all the possible permetations of cards that could come out. (A finite number as there are only 52 in a deck)

[WellChief]

Well if you know how many outs you have (estimation) then theres a quick formula that was in harringtons book.  You multiply the number of outs by 4 then subtract (no. of outs - .

ie if you have 15 outs (straight flush draw) then your % winning chance is 15*4 - (15 - = 53%

I think thats how they did it anyway. It's pretty accurate.

[Josh]

There's also one where after the flop, the first ten outs are 3% then anything in excess is 2.5% ...
Then after the turn all outs are 2.25% ? Or something along those lines.
Something explained on one of the many poker tv programmes.

[WellChief]

My one was for after the flop.  Your one is pretty inaccurate Josh, 14 outs should be 50/50ish but in your formula it only gives a 40% chance for 14 outs.

[NoflopsHomer]

Turn and river is roughly 4.4% per out, just the river is roughly 2.2% per out.

[Josh]

As I said, wasn't sure, was something along those lines, might have been slightly different percentages or for first 15 not first 10 outs, was mentioned by Roy Brindley on a show somewhere, but my pickled braind obviously has forgotten it.

[AdamM]

for speed I always just say outs x 4 after the flop, outs x 2.5 after turn. I think the most important part of the exersize is working out your LIVE outs.

[SupaMonkey]

I use the same flop calc as adam but i use 2*outs on the turn. It overestimates for 30% and above but not by much. I usually take off 1% for 30%, 2% for 40% etc.

[rivered]

yup same here, 4*outs after flop and 2*outs after turn....

[MrDigital]

Post flop generally just multiply x 4 for approximate %

or more accurate - first 8 cards of your outs at 4% and any others at 3%
i.e 15 outs = 8 x 4% + 7 x 3% = 53%

After turn exact odds per card is 2.2%
Easiest way to calculate is 2 x outs plus 2
So 2 x 15 outs = 30% + 2 =32%

Please correct me here if it's wrong don't want to misinform.. 

[stallyon]

but then how do you know what the percentage is based on your opponent having random unknown cards before seeing the flop?

[totalise]

but then how do you know what the percentage is based on your opponent having random unknown cards before seeing the flop?

IF you are referring to pokerstove, you select their range of hands.. so it isn't unknown. If the hand IS unknown.. ie random distribution, it enumerates all the possible flop/turn/river combinations and sees how often your hand does against each possible hand they have (if its a random distribution, they can have any two cards from AA to 23os)  and then gives you that figure as a percentage, effectively telling you how often you will win. if you want to know how to figure it out, you can use combinatorics quite easily to do it.. although its time consuming

If you are referring to the fact that sometimes your outs mite not be live (ie discarded from other players hands) then naturally this isn't known.. sometimes the deck will be light of cards that make ur hand, and sometimes it will be loaded with cards that make your hand.... this evens itself out over time, so you just go with what you know, which is your cards and the cards on the flop


If you are referring to something else, I cant figure it out from your post