Can Scientists Predict the Probability of Roulette Numbers?

Everyone who plays roulette would like to know which number has the best chance of coming up next. 

Still, is it possible to get some help from science in this respect and find out what number the ball is likely to drop into?

It’s a Game of Chance

The starting point for this look at roulette probability is by understanding that it’s a simple game of chance, so the goal should be only to have fun. This means that the outcome is completely random on every single spin of the wheel, and no one knows what will happen next. Even the croupier who spins the wheel has no idea what number the ball is most likely to land in.

How do casinos know that they’ll win money, though? Well, the house edge in roulette is produced through the fact that the payouts are titled very slightly in the favor of the casino, which means a small house edge appears over a large number of games. 

For example, in European versions of roulette, there are 37 pockets including the zero. Yet, the payout for correctly predicting which number will appear is 35 to 1. This means that a 2.70% house edge is present on any bet you make.

That’s doesn’t mean that you’ll always lose 2.70%. The house edge is something that becomes apparent over thousands of games, so if you  play a few games you could win or lose on every spin you make, which is what makes roulette so exciting.

The Gambler’s Fallacy 

A common belief among new gamblers is that the outcome of a previous spin affects what happens next. Let’s say that the ball lands on number 1, which is red, on the current game. You might believe that this means that there is a lower chance of the next spin being either 1 or red, or that it’s more likely to be even than odd.

However, the random nature of the games means that we can’t say this. The next outcome is just as likely to be red as it is black, and the same chance of being number 1 as 20, 14, or 35. You won’t often see the same number come up twice in a row simply because there are so many numbers on the wheel that could come up randomly.

This belief that the outcome of future spins depend in some way upon past results is known as the gambler’s fallacy. The simplest thing to remember is that the chance of any particular number coming up is exactly the same on every spin that you make.

Systems and Strategies

Roulette has been around since the 16th century, and it’s been incredibly popular during most of that time. This has led to players looking for ways to try and win at this game, and the easy access that the internet gives us to ideas has made it possible for players to look online for strategies and systems.

You’ll see various strategies mentioned as possible ways of increasing your chances of winning at this casino game. Some involve switching between different types of bet while others look for wheel bias or something in the dealer’s way of spinning the wheel that helps you to predict the outcome.

The truth is that there is no betting system that has been proven scientifically to improve your chance of picking the right number every time. The game is so cleverly designed that it might make you feel that you can find a way of winning more often, but it eventually comes down purely to luck.   

Some sources suggest that betting systems that manage your bankroll are the only way of getting a better chance of winning at roulette. Yet, even these strategies can fail if the wheel throws up several unexpected results in a row.


With the amount of analysis carried out on the roulette wheel before now, it seems certain that any chance of predicting the numbers more accurately would have been revealed. The fact that there is no scientific evidence in this respect means that we have to carry on viewing it as a game of chance where the player can’t do anything to more accurately predict the number that will arrive next.  

All you can do to have a better chance of winning at roulette is choose the version of the game and the bets that suit you. For instance, American roulette’s five number wager has the highest house edge while even money bets in European games with la partage or en prison rules give you the lowest house edge you’ll find anywhere.

Above all, it makes sense to view roulette as a form of entertainment that gives you the opportunity to win some money while enjoying the experience. This is one of the reasons why you should never wager more than you can afford to lose and should set a sensible wagering limit for every session of the game that you play. 

Written by Austin Crane

Austin is the principle web director for Untamed Science and Stone Age Man. He is also the web-director of the series for the High School biology, Middle Grades Science and Elementary Science content. When Austin isn't making amazing content for the web, he's out on his mountain bike or in a canoe.

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