ONLINE POKER 101: Step 5, Calculating Pot Odds
Posted by Pajamas Poker on November 25th, 2009In poker, pot odds are the ratio of the current size of the pot to the cost of a contemplated call. In other words, if the pot contains $100, and a player must call $10 to stay in the hand, then the player has 100-to-10, or 10-to-1 (commonly expressed as 10:1), pot odds. Pot odds are often compared to the probability of winning a hand with a future card in order to estimate the call's expected value. Indeed, a common usage of the term is to say that one "has pot odds", meaning that the present pot odds, compared to one's estimated chance of winning, make it profitable to call.
Converting pot odds to percentage values
Pot odds are a ratio, but having their percentage value will often make them easier to work with. The ratio has two numbers: the Size of the Pot, and the Cost of the Call. To get the percentage value, we add the Size of the Pot and the Cost of the Call numbers together and record their Sum. We then divide the Cost of the Call by the Sum. For example, the pot is $30, and the cost of the call is $10. The pot odds in this situation are 30:10, or 3:1 when simplified. To get the percentage, we add $30 plus $10 get a sum of $40. Now we divide $10 by $40, giving us 0.25, or 25 percent.
Using pot odds to determine expected value
When a player holds a drawing hand, or a hand that is behind now but is likely to win if a certain card is drawn, pot odds are used to determine the expected value of that hand when the player is faced with a bet.
The expected value of a call is determined by comparing the pot odds to the odds of drawing a card that wins the pot. When the odds of drawing a card that wins the pot are numerically higher than the pot odds, the call has a positive expectation; on average, you win a portion of the pot that is greater than the cost of the call. Conversely, if the odds of drawing a winning card are numerically lower than the pot odds, the call has a negative expectation, and you can expect to win less money on average than it costs to call the bet.
Implied pot odds
Implied pot odds, or simply implied odds, are calculated the same way as pot odds, but take into consideration estimated future betting. Implied odds are calculated in situations where the player expects to fold in the following round if the draw is missed, thereby losing no additional bets, but expects to gain additional bets when the draw is made. Since the player expects to always gain additional bets in later rounds when the draw is made, and never lose any additional bets when the draw is missed, the extra bets that the player expects to gain, excluding his own, can fairly be added to the current size of the pot. This adjusted pot value is known as the implied pot.
Manipulating pot odds
Often a player will bet to manipulate the pot odds offered to other players. A common example of manipulating pot odds is make a bet to protect a made hand that discourages opponents from chasing a drawing hand.
Bluffing frequency
According to David Sklansky, game theory shows that a player should bluff a percentage of the time equal to his opponent's pot odds to call the bluff. For example, in the final betting round, if the pot is $30 and a player is contemplating a $30 bet (which will give his opponent 2-to-1 pot odds for the call), the player should bluff half as often as he would bet for value (one out of three times).
However, this conclusion does not take into account some of the context of specific situations. A player's bluffing frequency often accounts for many different factors, particularly the tightness or looseness of their opponents. Bluffing against a tight player is more likely to induce a fold than bluffing against a loose player, who is more likely to call the bluff. Sklansky's strategy is an equilibrium strategy in the sense that it is optimal against someone playing an optimal strategy against it.
Online Tools
Calculating odds can be a daunting task for new poker players, and if you play online there’s no reason not to use one of the many tools out there to help you calculate pot odds on the fly. Tournament Indicator is a tool that allows you to instantly calculate pot odds, win odds, yours/opponent’s hands on the river, expected value, group, outs and position. Needless to say for the beginning and experienced player alike a tool like Tournament Indicator can be invaluable when playing in the fast-paced online games.
Calculatem Pro is another tool that you can use while playing online to do much of the heavy lifting. The tool itself works much like Tournament Indicator and also offers instant odds and gives you tons of information to help you make the best moves.
To read further on calculating pot odds and other required poker techniques we recommend you read David Sklansky’s “The Theory of Poker” and “No Limit Hold’em Theory and Practice.” For other tips about winning in online poker make sure to check out all of our Online Poker 101 stories.
