Slot Machine Probabilities
Probability makes slot machines unbeatable. No slot machine strategy guide or ebook is going to tell you that, because if more people understand that you simply can’t beat a slot machine, the slot machine strategy business would implode. But slot machines are impossible to beat in the long run.
But people win jackpots all the time–just last week my great aunt Dottie put one quarter in a slot machine at John Wayne and walked away with $2,500. Right?
Sure–any game is beatable in the short-term. But slot machines are unbeatable over time, just like baccarat, roulette, keno, and 3 card poker.
If you understand slot machine probability, you’ll realize that slots are best enjoyed on a whim, to kill some time waiting for a drink, or to get rid of a pocketful of quarters. Pulling the lever on a slot machine is a fun distraction, especially if you have no expectations of beating the slot machine.
Here’s a quick look at slot machine probability as it relates to the slot’s status as an unbeatable casino game.
What Makes Slots Unbeatable?
We call a casino game unbeatable when that game has a negative expectation. That means that no matter how much skill a gambler has, his probability of winning in the long run is less than 100%.
By that definition, almost every game in the casino is unbeatable–the only games that can provide a positive expectation is blackjack (if you’re counting cards) and some video poker variations (if you’re playing with perfect strategy).
Both of these games require perfect play by skilled gamblers in order to achieve a positive expectation.
Unfortunately for those of you hooked on the one-armed bandits, slot machines will always offer a negative expectation. That’s because they are programmed to offer the house a small but definite return. That’s what the payback percentages posted on some slot machines represent–the percentage of money put into the machine that gets paid back to the player. Ever seen a slot machine with 100% or greater payback? I thought not.
What Is Expected Return?
It’s possible to express the probability of winning any game on a percentage basis. If the expected return from a game is more than 100%, you’re playing a positive expectation game. If the expected return from a game is 100% on the nose, that’s a game with even odds. Once you dip below a 100% expectation, you’re playing in an unbeatable or negative expected return game.
To work out the expected return of a bet or a game, you take the probability of winning and you multiply it by the amount won over the amount wagered. Take a roulette wheel bet for example–a bet on black in roulette will win 18/38 of the time. That’s roughly 47% of the time.
If you spin the roulette wheel 100 times, you can only expect to win 47 times and lose each of the other 53 times.
Unbeatable Slot Machines
Because modern slot machines use weighted reel stops, where some stops on a slot machine’s reel will come up more often than others, the probability of landing on any one reel stop is different from the probability of landing on a different stop. A slot machine’s computer may only offer two out of 128 possible reel stops to the symbol needed for a jackpot. That means the odds of landing three of those jackpot symbols is 1 in 262,144. That means you’re only like to hit the maximum jackpot on this particular machine 0.00038% of the time.
The payouts for modern slot machines are designed to give the casino a built-in edge. Think of it like taking money out of a cookie jar. If every day you take $100 out of a cookie jar, and every night you put back $95, eventually that cookie jar would run dry. Slot machine probability works something like that, only in this analogy that cookie jar is your wallet.
Slot machine probability ensures that there’s no strategy or tactic that will help you win money on slot machines. No matter what you do, a slot’s programming will always make sure that the casino gets their cut, especially over the long-term.