Odds & Probability

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Why Odds & Probabilities are Important to Gamblers

If you want to gamble smart, then you need to understand a little bit about math, at least as it relates to probability and odds. A lot of people, especially in the USA, are notoriously math-averse, but the math involved in odds and probability calculations are honestly pretty straightforward and simple.

The main reason that you should understand a little bit about probability is also simple. The better you understand the nature of what you're doing (in this case, gambling), the more enjoyment you'll receive from that activity. And you cannot understand the nature of gambling without understanding a little bit about probability.

If You Really, Really Abhor Math

If you absolutely cannot stand math, and you want no part of learning the basics of probability, but you still want to gamble, then more power to you. I don't understand it, and I don't think you can be a "shrewd gambler" without some understanding of this subject, but I encourage you to bookmark this site anyway, ignore the math stuff, and just learn how to play the different games, make the different bets, and follow the basic strategies for the different gambling games and activities discussed here.

Some Odds and Probability Related Terms

Odds - The odds of something happening is the likelihood that something will happen. It's generally expressed as a ratio of probabilities.

An example of odds in action can be expressed when flipping a coin or rolling a six-sided die. The odds of getting heads when you flip a coin are even, or 1 to 1. There are only two possible outcomes, and there are even odds of the one outcome as the second outcome.

The odds of rolling a 6 on a six-sided die is 5 to 1. There are 5 outcomes that are NOT a 6, and one outcome that is a 6.

It's important to note that all casino games have payout odds that pay out less than the true odds. The difference in the odds that are paid out and the odds of your actual winning is where the casino makes its profit, and is referred to as the house edge.

Probability - A measure of how likely something is to occur. Probability is essentially the same thing as odds, but it's more often expressed as a fraction or a percentage.

The probability of flipping a coin and it landing on heads is 50%, or 1 in 2.

The probability of rolling a die and getting a 6 is 1/6, or 16.6%.

Payback percentage - This is the amount of money that a player is expected to win divided by the amount of money wagered. It's generally expressed as a percentage (hence the phrase "payback percentage"), and in the case of casinos games, it's almost always less than 100%.

House edge - The house edge is the difference between the payback percentage and 100%.

For example, if you're playing blackjack with perfect basic strategy with an ideal set of rules, the payback percentage is 99.5%. In that case, the house edge is 0.5%.

Over the long run, the house will win the amount of money wagered multiplied by the house edge.

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