Poker Odds & Probability

You know how to play basic poker and you understand the rules, but it is also important to know how much money you should bet, based on the odds and probability of your hand. Math and probability is an essential element for every decision you make in a game of poker, helping you to remain emotionally stable at the poker table, so you can focus on decisions instead of results.

 

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How Does Betting Work

To understand poker odds, it’s firstly important to know the basics of how betting in poker works. To start with, the small blind puts down half of the minimum bet, and the big blind follows with the full minimum bet. Blinds are generally set by the casino and it is made obvious when you sit at the table.

 

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If you’re playing no limit poker, then you have a choice of three options: call, raise and fold. ‘Call’ allows you to put as many chips as you like in the middle of the table, ‘raises’ allow players to add extra chips to be added to the table, instead of matching the initial call and a ‘fold’ is where a player leaves their cards face down, meaning they are no longer playing the game.

Poker Hand Rankings

Of course, you shouldn’t start betting until you understand the different poker hands and how they rank against each other. In a game of five-card poker, there are 2,598,960 possible combinations of hands when playing with a 52-card deck. Within this number of combinations, there are ten poker hands that you should know, when looking to bet in a game of poker.

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  1. Royal Flush – A royal flush is when you have 10-J-Q-K-A all of the same suit. It is the highest straight flush that you can possibly get in a game of poker.
  2. Straight Flush – A straight flush is when you get 5 cards all in the same suit. For example, 3-4-5-6-7 all of hearts.
  3. Four Of A Kind – Four of a kind is a combination of four of the same card. An example of this is when you have all four aces, or all four 2s.
  4. Full House – A full house is a set of three of the same card, plus two other cards that also match. For example, having three 9s and two 5s. If more than one player has a full house, the player who possesses the higher three of a kind (three of the same cards) out of the full house wins.
  5. Flush – A flush is when you have all of the same suit, which are not in order. An example of this is having a 5-8-9-Q-A of diamonds. If more than one player has a flush, the player with the highest card within their flush will win. If those cards match, then the next highest card will win and so on.
  6. Straight – A straight is when you have five cards that are all in a row but not in the same suit, such as 2-3-4-5-6, with one being hearts, two diamonds, one spade and one club.
  7. Three Of A Kind – A three of a kind is similar to a four of a kind, but with just three cards of the same card, such as three 3’s or three 5’s.
  8. Two Pair – A two pair is when you have two sets of pairs that have the same number within a hand. For example, having a hand that contains two 7’s and two 10’s. The higher the pair the more likely the winner is. If more than one player a two pair, then the one with the highest pair wins. If both pairs match between players, then the ‘kicker’ card will determine the winner. In this case, the kicker will be the fifth card that is not constituted in the two pair.
  9. One Pair – A pair, or one pair, is when two cards within a hand match, for example two A’s.
  10. High Card – If no one has any of the above hands, the player with the highest card in their hand will win. Just having an ace is sometimes enough, depending on everyone else’s hands. If two or more players have the same high card, and no other hands to play, then the next card will determine the winner.

Drawing Outs

At first, calculating your odds can be confusing but having a basic knowledge of poker odds and probability is vital, if you’re looking to play poker seriously. Knowing how to calculate your ‘outs’ is one of the most important, basic ways to start understanding how to improve your hand. ‘Outs’ are simply the cards that will help you to improve your hand, rather than simply trying to guess what your opponent may be holding.

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For example:
If your hand consists of an 8 and Q of hearts and the dealer has laid out an A of hearts, a 2 of hearts, an A of spades and a 9 of clubs, the likelihood of a winning hand (ignoring what your opponent may have) means you probably need to obtain any heart. You can see that there are four hearts on the table and in your hand, and with only thirteen cards in each suit this means there are 9 hearts possibly still available in the deck (again ignoring what your opponent may have). This means that you have 9 outs.

When it comes to poker, both online and in a casino, it is easier to calculate the odds based on what you can see, and what cards are potentially left in the deck. There are 52 cards in a deck, 2 cards are in your hand, and 4 cards have been dealt on the table. This leaves you with 46 unseen cards.With the hand that you have in the scenario above, the unseen cards are split into winners and losers. With 9 cards in the deck that will give you a win (calculated by your ‘outs’) and 37 cards that will cause you to lose, your odds of winning are 37:9. This simplified down is 4:1, or 20%.

Feeling Flush? Poker Hand Odds

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  1. Royal & Straight Flush – In 5-card poker, there are 40 possible chances of getting a straight flush (including the four royal flushes) meaning the probability of being dealt this is 0.0015%.
  2. Four Of A Kind – In 5-card poker, there are 624 possible hands that have four of a kind, and the probability of being dealt one is 0.024%.
  3. Full House – In 5-card poker, there are 3774 possible full houses, and the probability of being dealt one is around 0.1441%.
  4. Flush – In 5-card poker, there are 5108 possible flushes (not including a straight or royal flushes) and the probability of being dealt one is 0.196%.
  5. Straight – The probability of getting a straight, that is not a straight flush, is 0.39% as there are 10,240 possible straights in 5-card poker.
  6. Three Of A Kind – There are 54,912 possible three of a kind hands that are not also full houses or four of a kind, and the probability of being dealt one is 2.11%.
  7. Two Pair – In 5-card poker, there are 123,552 two pair hands and the probability of being dealt one is 4.75%.
  8. One Pair –In 5-card poker, there are 1,098,240 possible one pair hands and the probability of being dealt one is 42.26%.
  9. High Card – In 5-card poker, the possibility of being dealt a high card or no pair, out of the 2,598,960 is 50.11%.

 

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