Roulette is one of the most frequently played table games at online casinos, and is particularly popular in the live lobby. That’s not too surprising, as it follows a set of fairly comprehensible rules, especially if you stick to the evens bets, like red/black, or odd/even numbers. These types of bets keep things very straightforward for beginners, and keep the house edge very low, as there is an (almost) 50/50 chance of winning.

The D’Alembert Roulette Strategy is a common strategy that works when placing evens bets. The system is quite straightforward and starts with the player deciding on a set amount of money to act as a unit. All future bets are then decided based on the unit amount you’ve decided on, and whether you won or lost on the previous spin of the wheel.

We’ll dig into the details a little below, but it is a simple system for players at any level, so you’ll often find it used in online casinos, especially when playing live roulette.

The history of the D’Alembert Roulette Strategy

To trace the history of the D’Alembert strategy we must go back to the 18th century. The strategy is named for the French mathematician, philosopher and physicist, Jean le Rond d'Alembert, who made the argument (incorrectly, as it turned out) that in a game of heads or tails a coin is statistically more likely to land on heads if the previous toss landed on tails, and vice versa.

This can of course be applied to gambling, as in a game with a roughly 50/50 outcome, a win is more likely to follow a loss, and vice versa. While D’Alembert’s theory was inaccurate, the betting system based on it, over time, was widely adopted. The D’Alembert Roulette Strategy, along with other similar strategies such as the Martingale system, was regularly used by the end of the 1700s, and is still in use today.

How the D’Alembert Roulette Strategy works

When following the D’Alembert strategy, you first decide on a unit, which you use for each and every bet. This could be £1, £10, or anything else, which is why this is a strategy that can work for both high rollers and much more conservative gamblers. Each time you win the bet, you decrease the next bet by one unit. Each time you lose, you increase the next bet by one unit.

D'Alembert’s theory that each toss of the coin will likely be different to the last may not be correct, but the overall idea is simply that, over time, wins and losses will even out. So, over a long playing session, this system should limit losses and maximise wins.

Your odds of winning in roulette depend on the variant you’re playing, and there is always a slight house edge, but with an evens bet you are fairly close to a 50/50 chance, so it makes sense that systematically increasing and decreasing your bet allows you to manage both your chances of winning and your bankroll.

Using the D’Alembert Roulette Strategy

Let’s take a look at how the D’Alembert strategy actually works within a roulette game. We’ll assume for now that the unit you’re working with is £10. So, you place your first bet using your £10 stake. Here’s how the game could potentially play out:

First round loss: next bet is £20. Second round loss: next bet is £30. Third round win: next bet is £20. Fourth round win: next bet is £10. Fifth round loss: next bet is £20. Sixth round loss: next bet is £30.

And so on. It’s easy to see from this example how the strategy facilitates good bankroll management. It is also a more conservative betting strategy than, say, the Martingale system, which also relies on increasing and decreasing bets dependent on wins and losses, but suggests doubling your bet after a loss, rather than just increasing it by one unit.

The D’Alembert Roulette Strategy sequence

The progression of the sequence within a game is quite straightforward. You’re simply adding or subtracting a unit from your previous stake, so the maths is pretty simple, as long as you stick with a round number for your unit.

How well the system works will depend on what sort of luck you’re seeing on any given day, of course. You will find it works best when you see both wins and losses, fairly evenly spread across the game. In spite of statistics, it’s always possible to see a long string of losses, or indeed wins, but the D’Alembert strategy, like many betting strategies, assumes that no winning or losing streak can continue indefinitely.

The D’Alembert Roulette Strategy: wins and losses

With this system, as with any other, players can see both wins and losses during their playing session, and the overall session can result in either a win (more chips than you started with) or a loss (fewer chips than you started with).

For this reason, it’s important to know how many chips you’re starting with, and keep track of things during the game. It’s easy to assume as a gambler, that you are doing better than you really are, so keep track of your starting bankroll so you can get an idea of whether you’re winning or losing overall.

Remember that with any betting system, it’s still important to set a limit on your bankroll. This is, in effect, a budget for the current gambling session. If the budget is gone, it’s time to stop playing. No exceptions. Many gamblers also set themselves a ‘take profit’ point. That is, a point at which they have won a certain amount and will now stop playing. This is based on the idea that if they continue indefinitely, they will eventually lose everything they’ve won.

D’Alembert Roulette Strategy variants

The most popular variant of this system is the Reverse D’Alembert strategy. This strategy is — as you’d expect — the opposite of the classic D’Alembert strategy.

With this system you increase your bet by a unit after a win and decrease it by a unit after a loss. This works on the idea that you should capitalise on a winning streak and grow more cautious on a losing streak. In that way, it is more similar to a system such as the Parlay strategy.

Some gamblers also experiment a little with the concept of the D’Alembert system, using for example the Double Dozen D’Alembert for dozen bets or the Simple Street D’Alembert for street bets, but these systems are generally unproven. In our opinion, the system is definitely best when used only for evens bets.

Should you use the D’Alembert Roulette Strategy?

Roulette is a game of pure chance, so really the only opportunity you have to employ any strategy within the game is with betting systems. The D’Alembert Roulette Strategy is a solid betting system that helps you control your bankroll, and it works for players at any level, so it’s definitely worth considering. It’s just important to realise that it cannot actually help you win, or stop you from losing.