Roulette and Physics: Can You Predict the Wheel’s Spin?

Roulette has challenged the minds of countless gamers throughout history. Roulette was created in Paris in the 18th century and is one of the few casino games in which the odds are fixed. Unlike card games, where the odds fluctuate depending on the previous hand or which cards are drawn, with roulette there are a fixed number of equal segments on a wheel, and the ball can fall into any of them. Yet many gamers have tried to devise strategies that rely on the physics of the ball movement to see if there is a way to gain an advantage.

Physics can be used to calculate the trajectory of objects in movement. In theory, we can define these forces and the impacts on the ball to determine how long it will travel and where it could theoretically end up. There are loads of variables that must be factored into the equation, and it is not a simple calculation by any means. But the question beckons – is it possible to calculate where the ball will land?

Physics of Each Roulette Round

The dealer will spin the ball around the roulette wheel and then turn the roulette wheel in each round. The roulette wheel is built into a wooden frame, called the Stator, which remains stationary during the round. The dealer throws the ball onto a small track, located just outside the Stator.

As the ball spins around the track, it will gradually lose momentum and then veer off the track. The ball then travels across the Stator, where it either slides down the sloped Stator or collides into one of the 16 frets. These frets are diamond-shaped, with one longer axis and one shorter. They are placed in equidistance from each other around the Stator, and in alternating directions (longer edge perpendicular to the wheel and then parallel).

Most of the ball's trajectory is on the track, and once it falls down the stator and into the roulette wheel itself, it generally does not travel much. The ball eventually falls in line with the pockets, divided by small pocket frets, and either lands directly on one pocket or travels a few segments before coming to a halt. And it is your job to guess where the ball will land.

Gameplay Mechanics

The segments are all equally large on the wheel, and the roulette odds are fixed. Predicting the outcome of a spin only really becomes possible if you are playing at a real life table. And then, there are lots of variables to consider here. The most notable of which are:

• Ball Speed
• Wheel Turning Speed
• Time Ball Spends in Motion

We are solely referring to live roulette tables, where there are real balls on real roulette wheels thrown manually by croupiers. Now while loads of different aspects can affect the outcome of a wheel, there are some success stories of players using physics to beat the wheel.

These theories, for the most part, could not specifically calculate which segment the ball would land in. But they could get the sector (4-5 numbers), or the corner of the wheel (9-10 numbers). In terms of how much you could win, it would translate to the following.

• Sector Betting: 30x Winnings (5x spent to win 35x)
• Quarter Betting: 25x (10x spent to win 35x)

Roulette Physics Prediction Methods

We are going to run through a number of methods that have worked in the past at Roulette Wheels. Though you should note, that these methods, while scientific, used a lot of assumptions. They do not follow the standard probabilities and outcomes of the game. Instead, the systems pinpoint potential loopholes or biases that can “fix” the results.

Predicting the Sector Where the Ball will Fall

In 1961, card counting maverick Edward O. Thorp teamed up with Claude Shannon to build the first wearable computer. They wanted to specifically use it to time the ball spins and wheel spins, and use the information to determine which 1/3 of the table the ball would fall into. Taking the ball's average spin time, how fast the wheel spins, and the octant in which the ball is released onto the track. The computer could quickly calculate the possible octant where the ball would fall, and then the inventors quickly placed their bets.

They would only have a few seconds to place their bets, as dealers only allow bettors a short time when they can place last minute bets before they call “Rien ne va plus”, or “no more bets”.

Some 10 years later, a group of university students used computers concealed in their shoes to win at roulette. Thomas Bass documented the story in his book The Eudaemonic Pie. The book analysed how the Newtonian Laws of Motion determined the roulette balls' landing segment. The only snag about these methods is that they assume the ball speed and roulette wheel spinning speed are always uniform. They are thrown manually by croupiers, and while the force applied is nearly always the same, the small anomalies can ruin the theory.

Analysing Wheel Bias

In the early 1990s, another theory was born, but this time observing an entirely different physical phenomenon. Gonzalo Garcia Pelayo recorded the results of one table in the Casino de Madrid and analysed them through his computer. His theory was that the tables at the casino were not built perfectly.

They had some biases, specifically towards certain numbers or segments. After using the same roulette wheels for numerous years, they do tend to wear and tear, and there may be instances where the ball will fall more regularly into specific pockets. He tested his theory on that same wheel in the Madrid casino and won 600,000 euros in one day.

This theory is quite sound, but given that nowadays tables are built to reduce these anomalies and to nearly always bring random results, it is very difficult to test. You could, in theory, try to analyse the history of one roulette wheel. However, you would need to simulate thousands of results to get any results. Even then, they will not be very precise.

Are Physics Related Strategies Still Relevant Today?

There are still stories that come out today about players using physics to win roulette. Whether it is playing biased wheels or using computers to calculate where the ball will fall, it can still happen. Though the roulette wheels nowadays are designed to be more random and difficult to predict. Those diamond-shaped frets, low slope, and dynamics of the wheel have all been optimised to reduce the predictability of where the ball will spin.

We have even heard stories of players claiming that dealers “aimed” for specific segments. Both in favour of the players (for the tips) or to deliberately make the player fail, but these are not true. There are so many variables that come into play. Even if the dealer could perfectly throw the ball and spin the wheel at the same trajectory each round without fault, the wheel is designed to create random results.

Legality of Physics-Based Roulette Gaming

In 2024, there was an incident at the Ritz London Casino, where three players used laser scanners in their mobile phones to predict where the ball would land on a roulette wheel. Their phones calculated the possible sectors, and the group made £1.3 million in two nights. They were arrested following their exploits, but then released and allowed to keep their winnings.

The key thing to note here is that no casino equipment was damaged. Garcia-Pelayo did not damage the roulette wheel at the Casino de Madrid either. The casino tried to sue him, but the court ruled that they were at fault for providing a biased casino wheel.

It is not illegal to try to calculate the sector or octant where a ball will fall. But if you make a fortune doing so, there may be consequences. Casinos have the right to ask players to leave if they are suspected of fraudulent activity. This goes for card counters at blackjack or even arbitrage bettors at sportsbooks. In some scenarios, the casinos may even suspend or ban you from coming back. But if you win a truly gigantic sum of money, they may even take legal action.

However, it is a very rare scenario in which a casino takes legal action against a gamer. If you have a method based on physics, just make sure you are playing by the rules and not abusing the games. The casinos are watching your every move through their surveillance systems. You cannot damage the gaming tables or disturb your peers either.

Alternative Strategies for Roulette Players

We are not saying that it is completely impossible to predict the sector where a ball may fall. A lot of gamers place their roulette bets based on where the numbers are on the wheel. Instead of their position on the paytable (yes, they are different). Or, they use call bets (or announced bets), which define specific segments of the wheel. These include Jeu Zero, Viosins du Zero, Orphelins, and Tiers du Cylindre.

You can always try to cover specific segments of the wheel, hoping that the ball will gravitate towards them. However, never forget that the table is designed to bring random results.

The alternative roulette betting strategies relate to how much you stake per round. The most famous of these is the martingale betting strategy, whereby you double your stake after each loss. The idea is that once you end your losing streak and win, you will claim back all your losses. However, players need a massive budget to play the martingale system successfully. Plus, roulette table limits can also affect how far you can go with your martingale plan.

The martingale system is not the only one that roulette players can use. Other systems such as the Fibonacci method, Paroli and Labouchere systems play around with how much you stake, with both increases and decreases based on what happened in the previous rounds.

Each of these methods has its own applications. For instance, the D'Alembert levels out your winning/losing by doubling up after a loss and halving after every win. Labouchere is designed using a series of numbers in a line that determines your betting amount. These flexible progressions change the speed at which players will win and lose.

Concluding Roulette Betting Systems

There are no rules against betting on specific segments of the table. You can try it for yourself, it may even bring you more wins. But don't bank on tables or dealers to have any biases. Remember always to play responsibly and never spend money that you cannot afford to lose. Each round is independent from the previous, and you can never pinpoint the exact segment where the ball will fall. Don't make any assumptions, and certainly don't fall into the gambler's fallacy of assuming there are “hot” and “cold” segments.

Focus on the areas where you have control. Namely, in how much you stake, and when you decide to call it quits. First, make a fault-proof roulette bankroll, that can sustain longer periods of gameplay. Next, learn when to call it quits. That way you will avoid heavy losses and can benefit from any ground you have won.