Calculating Poker Odds

Poker may seem like a game of chance to some, but realistically, it's no such thing. Poker, like everything, is made up of a series of mathematical probabilities, and the players who are able to fire out these sorts of calculations in their heads tend to be the same players steamrolling tournaments on a regular basis. Poker Insider has investigated for you, and here's what we've found.

The odds of opponent behaviour

When playing against someone over many hands, such as in a tournament, it's worth noting that they're likely to form patterns with their behaviour. A common example is the player who bluffs once for every three times they don't. Simply put, this means that at least 25% of the time, or one in four, you're likely to have a better hand than they do. Although this 1 in 4 probability is the same for every hand and never changes, you're also statistically better off, therefore, with someone who bluffs every other hand, as this raises your odds to 2:1, rather than 4:1.

Estimating hands using bets

It's also very possible to accurately estimate how good someone's hand is, based on how they're currently betting. If the pot is $20, and they've bet $8, the probability mathematics behind that level of betting over time would indicate that this person has a worse hand than someone who would bet $10, or even $20. However, if someone goes all in on either a huge bluff or a seriously high pair of cards, then it's worth reconsidering.

Calculating an opponent's hand

If we consider for a moment that there are 52 cards (minus the jokers) in a deck of cards, we know that there are 50 we are not aware of before the flop. However, once the flop goes down, followed by Fourth and Fifth Street, this means there are now only 47 cards we do not know the identity of. This seems like steep odds when it comes to predicting what cards you are up against, but if you learn the numbers before hand, you can act upon them. For example, there is a 220 to 1 chance of pocket aces, and therefore a one in 221 chance of getting that hand on the deal. However, going on the cards that would improve your hand is the smart move, as this narrows down the probability significantly.

It doesn't always work

Accept that probability mathematics in poker is fallible. Sure, you may have a 9 in 10 chance of winning with this particular hand, but realistically, there's still that 10%, and you'll soon find that relying solely on the mathematical probability of cards may lead to some upsetting revelations once the chips are down.

So get your maths hat on and study, as even if it is fallible, poker mathematics can make you a more logical and talented poker player - especially if you're shooting for the big leagues.