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What can I do to calculate my odds in a hand?
If I have 2 cards of the same suit in the hole, and 2 board cards with those suits on the flop, what are the chances that I will hit my flush:
- On the turn?
- By the end of the hand?
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What can I do to calculate my odds in a hand?
If I have 2 cards of the same suit in the hole, and 2 board cards with those suits on the flop, what are the chances that I will hit my flush:
After the flop you've seen 4 cards of your suit, and 1 of another suit. This leaves 9 cards of your suit, and 38 of a different suit; your odds of completing your flush on the turn are thus 9/47
, or 19.14%
.
If the turn hasn't completed your flush, your odds of completing it on the river are 9/46
, or 19.5%
.
This means that the total odds for completing a flush - which should matter for example if you're going all in after the flop - are (19.14%) + (19.5%*(1-19.14%)) = 34.96%
(the odds of completing on the turn, plus the odds of completing on the river times the odds of not completing on the turn).
A good rule of thumb I always use for a flush draw is multiply outs(13 spades - 4 spades) with 4 on the flop and 2 on the turn. This ways it's much easier to remember and you aren't that far away from the correct percentage.
That is:
On the flop = number of flush outs x 4 = (13-4)x 4 = 36%
On the turn = number of flush outs x 2 = (13-4)x 2 = 18%
Obviously a "naked" flush draw is not a very good hand to move all-in with on the flop since you are most likely to be up against a much stronger hand if your opponent raises you. However, if you are holding a flush draw as well as two cards that are higher than the cards on the flop, this is a much stronger hand since you are drawing to a higher pair versus a potential top pair on the flop.
example: s = spade.
AsKs vs 88
flop: 4s 7h 2s
here you have 9 outs for the flush + 3 aces and 3 kings to hit against his pair of eights. This works out to a total of 9+3+3 = 15 outs => 15 x 4 = 60% .. although the correct answer is a bit smaller.. so 55% is more accurate.
My conclusion is that if you really "have to" move all-in with a flush draw, you should do it with two high cards of the same suit! :)
Here is a nice tool called pro poker tools.com to help you calculate your chances!