D’Alembert System Explained – What is the D’Alembert System?

The D’Alembert system helps you stay in control of your bankroll when playing games such as baccarat, blackjack and roulette. It is a low-risk approach, designed to grind out small wins and chase down losses. The D’Alembert is a lot less aggressive than strategies such as the Martingale, and it is well suited to certain players.

This guide explains how to use the D’Alembert betting system. We will provide examples to show you how the strategy works in practice. You will also discover the games it can be applied to and the best online casinos to register with if you want to try it out.

What is the D’Alembert System?

The D’Alembert is a negative progression system that tells you how much to wager when playing popular casino games. It can be applied to any even chance bet, such as red/black on the roulette wheel, pass/don’t pass on the craps table, the player bet on a baccarat game or a hand at the blackjack table.

D'Alembert System When Playing Live Dealer Immersive Roulette

It is pretty straightforward. You simply increase the size of your bet after you lose, and you decrease your bet amount after a win. The idea is to chase down your previous losses, while also racking up several small wins.

Test this strategy out with a massive welcome bonus – sign up at Wild Casino today.

How Does the D’Alembert  System Work?

As is the case with all betting systems, you can start by putting together a bankroll. This is the money you will use for a session at an offshore online casino. You can then set a percentage of that bankroll as your base unit.

For example, let’s say you have a bankroll of $1,000, and you might decide to make your base unit 2%, which is $20. In that case, you would begin by placing a 1 unit bet for $20 on your chosen game.

The D’Alembert system simply requires you to increase your bet amount by 1 unit after a loss, and you decrease it by a unit after a win. The next section shows the D’Alembert approach in action.

D’Alembert System Example

The chart below highlights a theoretical session at an online casino when using the D’Alembert betting strategy. It assumes your base unit is $20. The first column shows your bet amount, and the third column shows your overall profit or loss.

Bet Result Profit / Loss
$20 Win $20
$20 Win $40
$20 Loss $20
$40 Loss -$20
$60 Loss -$80
$80 Win $0
$60 Win $60
$40 Loss $20
$60 Loss -$40
$80 Win $40
$60 Loss -$20
$80 Loss -$100
$100 Loss -$200
$120 Win -$80
$100 Win $20
$80 Win $100

In this example, you have placed 16 bets, with eight wins and eight losses, and ended up with a $100 profit. By contrast, had you maintained the same stake for each bet, you would be flat for the session, without a profit or loss.

It shows how the D’Alembert can be used to grind out small wins, without ever needing to place huge bets – as is the case with alternative systems such as the Martingale.

How about using the D’Alembert strategy live? Play with real dealers at Bovada.

D’Alembert System Pros and Cons

There are always advantages and disadvantages to any betting system. These are the main pros and cons to bear in mind when following the D’Alembert strategy:


  • This system will appeal to anyone who likes the idea of chasing previous losses and canceling most of them out with one bet.
  • It is designed to help you earn a series of small wins, as it does not require you to increase your bet amount after you win.
  • You do not need a huge bankroll to use the D’Alembert, and table limits are unlikely to be a problem either, as is the case with the Martingale.
  • This approach is simple to follow, unlike alternative systems such as the Fibonacci, so you can concentrate on enjoying the game.
  • It gives you a measure of control over your bankroll, as opposed to blindly choosing random bet amounts.
  • The D’Alembert can lead to long sessions, helping you earn lots of loyalty program points.


  • The creator’s assertion has been debunked and it is now referred to as the gambler’s fallacy.
  • You will not necessarily wipe out all previous losses with a win when using this system, whereas the Martingale does cancel out all previous losses.
  • While it is relatively low-risk, you may end up placing large bets if you go on a losing streak, which can be daunting for some players.
  • This system does not make the most of winning streaks, as you decrease your bet amount after each win.
  • You can only use this approach on even chance bets.

D’Alembert System for Roulette

You can use the D’Alembert on any bet where there are two potential outcomes: you either lose your bet, or you win and double your money. These are known as even money, even chance or 1:1 bets. There are three key options when playing roulette:

  • Red or Black
  • Odd or Even
  • High (19-36) or Low (1-18)

Roulette Betting D'Alembert

Red/black is the most common bet on a roulette wheel. If you want to follow the D’Alembert betting system, start by wagering 1 unit on red or black. Increase by a unit if you lose, and continue. If you win, decrease by a unit.

D’Alembert Betting System for Blackjack

Blackjack is a popular table game with a high Return to Player (RTP) rate. Most blackjack games have an RTP of more than 99%, so it is a great option for anyone pursuing betting systems. In general, you can either lose your bet or double your money when playing blackjack, so you can simply use the D’Alembert to determine your bet on each hand.

D'Alembert System Used at a FanDuel Live Blackjack Table

As always, start by betting a single unit, and then go up or down depending on whether you win or lose. It can get more complicated if you double down or split cards. However, if you double down and lose, you can always increase your stake by 2 units, and you can decrease it by 2 units if you double down and win. The same is true if you split cards and either win both or lose both hands.

Looking for engaging and thrilling blackjack titles? Register with Everygame.

D’Alembert System for Other Casino Games

The D’Alembert also lends itself well to baccarat, another high RTP game available at online casinos. If you want to use it on the baccarat table, the player bet is the best option, as you double your money if you win, and it has a high RTP.

Craps also works well for betting systems, provided you stick to bets such as pass/don’t pass or come/don’t come. You can also use the D’Alembert on basic, high RTP slots without huge bonus features and with low variance, but it is far better suited to table games.

D’Alembert for Sports Betting

Some sports bettors might like to use the D’Alembert, as it can improve your bankroll management. If so, simply place a bet with 1 unit, and then increase your stake by 1 unit if you lose, and decrease it by 1 unit if you win.

However, it will only work neatly if you place even money (+100) bets, which are rarely available. Most online sportsbooks take a 4.77% house edge – known as the vig – on their sides and totals, so you need to bet $110 to win $100. It means the bets do not offer a 1:1 payout, and you need to win around 55% of the time to end up in profit.

Sports betting at BetOnline.

For that reason, your profit/loss column may look a little disorderly if you pursue the D’Alembert when betting on sports. Yet the concept of increasing your bets after a loss and reducing them after a win may appeal to some bettors.

Reverse D’Alembert

The Reverse D’Alembert is a positive progression strategy. It is simply the polar opposite of the D’Alembert. You increase your bet amount after a win, and you decrease it after a loss.

This approach does try to capitalize on winning streaks, and it does not chase losses to the same degree. Some players prefer increasing their stakes after winning rather than losing. If so, the Reverse D’Alembert may be the approach for you. It is less risky than the Reverse Martingale, but it is not as popular as the Paroli, which is discussed in the next section.

Alternatives to the D’Alembert

The D’Alembert is a steady, low-risk negative progression strategy. It is popular with online casino players, but you may find an alternative approach more appealing. These are some alternative negative progression systems:

  • Martingale System | This approach requires you to double the size of your bet amount after a loss, and go back to 1 unit bets if you win. The idea is to wipe out all previous losses in one fell swoop, while also accumulating small wins. It is more aggressive than the D’Alembert, but it is also more rigorous.
  • Fibonacci System | This approach follows Fibonacci’s famous sequence – 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233 and so on. You start at the beginning of the sequence, betting 1 unit, and move forward one step after each loss and back two steps when you win. It can quickly lead to large bets if you go on a losing streak, but the system is designed to wipe out losses quickly.
  • Labouchere System | This approach requires you to choose the amount you would like to win, such as $200, and break it down into any sequence, such as 20-50-50-20-10-20-30. You begin by adding the first and last numbers together, and that forms your initial stake. If you win, cross those off and add the new numbers at either end of the sequence together to form your next stake. If you lose, simply add your bet amount to one  end of the sequence and continue.

You may instead prefer to try a positive progression strategy, which is designed to capitalize on winning streaks. These systems do not chase losses. These are some of the most popular methods:

  • Paroli System | Each time you win a bet, increase your stake by 1 unit. If you win three consecutive bets in a row, return to the start and wager 1 unit again.
  • Reverse Martingale System | This is an aggressive approach, whereby you double your bet amount after each win. It means that a single loss would cancel out all of your previous wins, so it is important to quit when you are ahead if pursuing the Reverse Martingale system.
  • 1-3-2-6 System | Bet 1 unit, then 3 units, 2 units and 6 units, and then go back to the start and wager 1 unit again. Only move along with sequence if you win, as it is a positive progressive approach.
  • Oscar’s Grind | An approach that encourages you to increase your stake by 1 unit after each win and maintain the same stake when you lose. When you earn at least 1 unit in profit, return to the start and bet 1 unit again.

D’Alembert System History: 18th Century Origins

Jean-Baptiste le Rond D’Alembert, a prominent French mathematician in the 18th century, devised his eponymous system. He was convinced that if a coin toss results in heads, the next flip would be more likely to result in tails, so he encouraged larger bets after a loss and small bets after a win.

This assumption has since been disproved, and it is widely referred to as the gambler’s fallacy. Yet the D’Alembert system remains popular, and it does offer certain advantages to casino players, as we will explore in the next few sections.


What is the advantage of the D’Alembert system?

Is the D’Alembert system allowed in casinos?

What is the D’Alembert system in roulette?

Is the D’Alembert a good strategy?


Sam Barnard

Sam is the Gambling Law Expert on Techopedia.com, and has been working in the sports and gambling industries for more than a decade across many North American and European sites such as Casino.org, SportBusiness.com and Coral bookmakers. An expert on US gambling regulations, Sam oversees content on the site.