First, you derive the percentage of the bet you have to call compared to the size of the pot. Next, count your outs to determine your chances of catching your card.
Then, multiply that number by four if the turn and the river are still to come, or multiply by two if just the river remains. That number is close enough to give you the percentage that you'll hit the card you need.
If your odds of catching your card are greater than the bet you have to call, then pot odds dictate that you make the call.
A real-life example came in a hand between top pros Jennifer Harman and Carlos Mortensen during the 2006 World Poker Tour Championship at Las Vegas' Bellagio in April.
With blinds at $800-$1,600, plus a $200 ante, Mortensen drew Q-Q in middle position. Mortensen, who won the 2001 World Series of Poker main event, raised to $5,000.
Action folded around to Harman, who called Mortensen with A-9 suited from the big blind.
The flop came Q-J-8 with two hearts. Harman, who has won two WSOP bracelets, checked with a flush draw and gutshot straight draw. With a set of queens, Mortensen bet $10,000.
Harman raised him $20,000 more. “I was hoping he'd lay his hand down because the pot was big enough,” Harman says of a pot that contained almost $25,000 before her raise.
But Mortensen did not fold. Nope, he moved all in.
The pot now held almost $125,000. Harman faced a call of an additional $50,000.
“I think I priced myself in to call,” says Harman, a regular in the “Big Game” at the Bellagio with the likes of Doyle Brunson, Chip Reese and Phil Ivey.
Harman was getting 2.5-1 on her money (a $50,000 call into a $125,000 pot). But with nine unseen hearts to make a flush and the other three non-heart 10s to make a straight, Harman had 12 outs.
Multiply the 12 outs times four because the turn and river were still to come, and you get 48 percent, making Harman almost even-money. If her ace was any good, she had another three outs to make this an easy call.
The turn came one of the 10s that Harman needed, and when the river came a blank, Mortensen was out.
“I made a straight and I busted my friend, Carlos,” Harman says. “I felt bad that I busted my friend. I hate to show my sensitive side. There are certain people I don't like to bust. If I beat him, fine. I don't like to bust him.
“The only way I wouldn't call is if I wouldn't want to bust him, and I can't do that. I may be sensitive, but I'm not stupid.”
Gutshot straight draw: Needing one of the inside cards to make the hand; for example, 8-9-x-J-Q.
© 2007, Chicago Tribune.
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