backdoor flush/straight odds

AlfieAA

AlfieAA

Legend
Silver Level
Joined
Mar 17, 2012
Total posts
10,689
Awards
4
Chips
0
hi, ive just started learning pot odds and outs. ive got the basics down, i.e 9 outs for a flush 8 for a straight etc....but how do you calculate pot odds for a backdoor straight or flush?....or do you wait to see what comes on the turn first then make a one card decision...thanks
 
C

CANDYMAN1414

Rock Star
Silver Level
Joined
Jul 30, 2012
Total posts
143
Chips
0
not very good and betting on a gut shot is bad unless you have a flush draw or a pair with it.
 
Daniel72

Daniel72

Legend
Bronze Level
Joined
Aug 10, 2010
Total posts
2,284
Awards
2
Chips
18
A back door flush/straight is not a gut shot, candyman :)
 
B

BlueNowhere

Legend
Silver Level
Joined
Sep 1, 2011
Total posts
4,234
Chips
0
Say for example you want a backdoor diamond FD you would need a diamond on the turn and the river. The card that comes on the river is independant to the card that comes on the turn so we can use the formula P (A and B) = P(A)*P(B)

So say you have Jd5d on a 3d4c8h board to calculate probabilty it is just the chance of a diamond on the turn (10 in the deck of 47 cards) multiplied by chance of diamond on river (9 in deck of 46 cards). So (10/47)*(9/46) = 4.16% or 25/1.

Same can be done for BD straights.

I wouldn't worry too much about thinking about your BDs in real time. Sometimes the extra 4% equity leads me to jam some flops but I play a primarily shortstack game so I'm thinking about my current equitywith jamming so BDs are relevant. When you play a few more street your immediate equity isn't really as relevant (although it is obviously still relevant) since you still have more money behind and you think more about how turn cards change your equity. I can sometimes float some boards with BD draws but at an early level in poker I take it more on a street by street basis and wouldn't really give thought to multi-street plans.

Not sure I'm putting across what I mean as eloquently as I'd like. Not 100% sure my explanations look sound. I'm good at Maths and Science, not things like English that involve good writing skills lol.
 
Last edited:
slgalt

slgalt

Rock Star
Silver Level
Joined
Jan 9, 2008
Total posts
233
Chips
0
I think if you're just starting out then learn to fold, holding out for a backdoor possibility without thinking about implied odds etc, is a beginner mistake. Once you learn the game you can think about adding it back into your play.
 
AlfieAA

AlfieAA

Legend
Silver Level
Joined
Mar 17, 2012
Total posts
10,689
Awards
4
Chips
0
Say for example you want a backdoor diamond FD you would need a diamond on the turn and the river. The card that comes on the river is independant to the card that comes on the turn so we can use the formula P (A and B) = P(A)*P(B)

So say you have Jd5d on a 3d4c8h board to calculate probabilty it is just the chance of a diamond on the turn (10 in the deck of 47 cards) multiplied by chance of diamond on river (9 in deck of 46 cards). So (10/47)*(9/46) = 4.16% or 25/1.

Same can be done for BD straights.

I wouldn't worry too much about thinking about your BDs in real time. Sometimes the extra 4% equity leads me to jam some flops but I play a primarily shortstack game so I'm thinking about my current equitywith jamming so BDs are relevant. When you play a few more street your immediate equity isn't really as relevant (although it is obviously still relevant) since you still have more money behind and you think more about how turn cards change your equity. I can sometimes float some boards with BD draws but at an early level in poker I take it more on a street by street basis and wouldn't really give thought to multi-street plans.

Not sure I'm putting across what I mean as eloquently as I'd like. Not 100% sure my explanations look sound. I'm good at Maths and Science, not things like English that involve good writing skills lol.

thanks bluenowhere, very interesting answer and although i dont understand the math behind it yet, i will keep in mind its 25/1 and not much point in continuing play in that situation, instead taking it one street at a time...cheers :)
 
AlfieAA

AlfieAA

Legend
Silver Level
Joined
Mar 17, 2012
Total posts
10,689
Awards
4
Chips
0
@slgalt yeah, ive not covered implied odds yet, but im assuming unless 9 people were still in the pot the chances of getting pot odds of 25/1 are impossible.
 
Full Flush Poker Poker Odds - Pot & Implied Odds - Odds Calculator
Top