What Is The D’Alembert System?

The D’Alembert betting system is a strategy that many gamblers use when it comes to placing bets.

While some prefer to gamble using gut instinct or lucky numbers, others prefer to take a more controlled and systematic approach.

The D’Alembert strategy is just one of a handful of popular betting strategies out there. But, it is generally considered to be the most conservative and least risky due to the formula it uses.

So, does the D’Alembert system work? Let’s take a look at it in more detail, what it is, how to play it, and the advantages and disadvantages of implementing it.

What Is The D’Alembert Betting System?

The D’Alembert formula entails increasing and decreasing your betting stake depending on the outcome of the previous bet.

Most betting strategies centre around the same concept but differ in terms of when to increase or decrease the stake and by how much.

The D’Alembert strategy is known as a negative progression system because you reduce your betting stake after a win and increase it after a loss. How much you increase and decrease the bet is all focused on betting units.

To determine what betting unit to start with, it's best to take a percentage of your overall budget. For example, if you have an overall budget of £100, then your base unit should be between £2 - £5 per bet. If you have a bigger budget of £1000, then your base unit would be £20 - £50.

The D’Alembert system is often referred to as a less aggressive form of the Martingale Strategy, which is probably the most well-known betting strategy in the world. While the Martingale system requires you to double your stakes after a loss, the D’Alembert system increases the bet by just one unit.

For example, if your original betting unit is £5, then after a loss you’d increase it to £10, and then £15 and £20. With the Martingale system, this would be £5, £10, £20, and then £40.

With both systems, you never decrease the bet lower than your original betting unit.

Where Did The D’Alembert Strategy Originate?

The D’Alembert betting system is based on a mathematical formula originally conceived by Jean Baptiste Le Rond D’Alembert.

D’Alembert was a French philosopher and writer and achieved fame as a mathematician and scientist before contributing and editing the famous 18th-century Encyclopédie.

The concept of the system was based on the premise that if you win roughly the same number of bets as you lose, then you should come out ahead as your winning bets will be at higher stakes than your losing bets.

Where Can The D’Alembert Gambling System Be Used?

If you’re looking to implement the D’Alembert formula into your gambling strategy then you need to look for bets that pay even odds or as close to it as possible.

D’Alembert is used most commonly in the outside bets in roulette. Bets such as red/black, odd/even, high/low come with just under a 50% chance of winning and pay 1:1 odds.

Obviously house edge will always factor into these bets, for example, a bet on odd or even on a single zero roulette game gives a 48.65% chance of winning rather than 50%. But it is close enough for the D’Alembert formula to be applied.

Other casino games that you can use the strategy on include baccarat, when betting on the player or the banker, craps on the pass/do not pass bet, and blackjack.

For those who enjoy sports betting, you can actually apply the D’Alembert strategy to your sports wagers too. Again, you should only use it on bets that come with as close to a 50/50 chance as possible. An example of this could be the over/under market of corners in a football match as they are usually very even odds wise.

If you win your bet, then you would reduce the stake by one unit for the next bet and increase it by one unit when you lose.

How To Use The D’Alembert System

Now we know the basic principles of the D’Alembert system, let’s take a look at it in practice.

We will lay out four different scenarios when betting on red or black in roulette using the D’Alembert strategy. The system does not require you to choose the same outcome on each bet, only to stick to the same bet type.

For these scenarios, we are using £10 as one single betting unit.

Scenario 1 – You win three bets in a row

With the D’Alembert strategy, you reduce your stake size by one unit when you win, but you never bet lower than your original unit. Therefore, in this scenario of winning three times in a row, your bet size remains at the original unit size of £10.

Although this situation would result in a £30 profit, it could be much higher if you were using a positive progressive system which would increase your bet size when you win. Winning streaks are therefore not capitalised on fully with the D’Alembert strategy.

Scenario 2 – You win two bets and lose the next three bets

In scenario two, your first three bets are at the original stake because you were winning. However, as soon as you lose, you increase your bet size by one unit to £20 and then to £30 after another loss.

Although this is more conservative than say the Martingale Strategy, which requires you to double your stake after every loss, it is still possible to be down by quite a bit after just a few losses. And with having to lower your bet size after a win, it can be difficult to recoup the losses quickly with the D’Alembert system.

Scenario 3 – You alternate between winning and losing bets

In this scenario, with a slight majority of wins over losses, it is possible to grind out a small win and keep losses to a minimum. That’s the whole philosophy of the D’Alembert strategy. However, it does not protect against a losing streak.

The smaller wins that can be achieved also don’t guarantee that you can cover any significant losses. The conservative approach, therefore, can be a downside.

Scenario 4 – You place ten bets with a mix of wins and losses

As you can see from this scenario, if you get a mixture of wins and losses, it is possible to play for quite a long time using the D’Alembert strategy. It also doesn’t require you to undertake huge jumps in betting stakes which can be really risky.

However, it can feel like a very slow and arduous process constantly upping and then reducing the bet size after each spin. It almost takes the fun out of gambling full stop and still doesn’t guarantee that you’ll come out with anything worthwhile at the end of it.

If anything, these four scenarios and their outcomes show just how inconsistent the D’Alembert strategy can be. The results include profits of £30 and £10 but also a loss of £40, so there is no security when using the system.

D’Alembert Strategy And The Gambling Fallacy

All negative progressive betting strategies are based on a concept that is fundamentally inaccurate. It is what we know now as the gambling fallacy.

The gambling fallacy is the incorrect presumption that in a 50/50 situation, if one outcome has landed, there is more chance of the alternative outcome landing next.

The easiest example is that of a coin toss. If two ‘heads’ have landed in a row, then the gambling fallacy refers to thinking there’s more chance of ‘tails’ landing on the third toss. However, statistically there is the same 50/50 chance that it could be heads or tails.

This is the root of negative progressive systems such as the D’Alembert system. The reason it requires you to lower your bet size after a win, is because the gambling fallacy believes there’s more chance that the next bet will be a loss.

Similarly, If you have just lost a bet, it requires you to double your next bet as the strategy considers there to be a higher probability of a win on the next bet.

This is something to be aware of when implementing the D’Alembert strategy. In a 50/50 situation, every bet is in isolation to the one before it and the one after it. A roulette wheel has no memory, so one spin cannot affect the next one.

Assuming that 50/50 outcomes will form a pattern, one that can be predicted and acted upon is a fundamental flaw in the D’Alembert strategy and others like it.

Pros And Cons Of The D’Alembert Betting System

There are benefits to using a system such as the D’Alembert betting strategy. However, it also has limitations and disadvantages too, which we’ll go into below.

Pros

• Suitable for small stakes – you decide what your initial betting unit is based on your budget. It can be as little as £1 so doesn’t need a large bankroll

• Simple – increasing and decreasing your bet size by one unit is simple to remember

• Limits losses - by only moving up and down by one unit at a time, it means losses are gradual and don’t jump too suddenly. You can still hit a losing streak, but it's more controlled

• Conservative system – the D’Alembert system can be good for bankroll management as it is so measured. There is nothing too drastic in terms of betting stakes and as long as there’s a mix of wins and losses it can keep you playing

• Adaptive – it is suitable for both casino games and sports betting as long as you stick to even odds

Cons

• Gambling fallacy – the system is based on a premise that is proven to be incorrect

• Slow – the D’Alembert system can be a slow and long process that requires concentration and patience while playing

• Chasing losses – the system requires you to chase losses but also limits how much you bet so covering losses can take longer than other negative progressive systems

• High losses are still a risk – depending on your unit betting stake, high losses are still a possibility if you hit a bad streak. If your betting unit is £20, and you lose four bets in a row, your fifth betting stake will be £100 so it can rise quickly

• Winning streaks not maximised – by decreasing your bet size when you win, the D’Alembert strategy sacrifices potentially highly profitable winning steaks

Tips On Using The D’Alembert Betting System

Choose the right betting unit for you – the whole D’Alembert system is based on a betting unit stake that suits your budget. Go too high and it might get very uncomfortable if you hit a few losses. Go too low and it will feel tedious adding or removing one unit at a time. The best guide is to choose between 2 – 5% of your overall budget, this should give you some wriggle room.

Stick to even money bets – the system only applies to 50/50 bets, or as close to 50/50 as possible. Moving away from these bets makes the strategy unworkable.

Stay disciplined – if you truly want to put the D’Alembert strategy to the test, then you have to stay focused and stick to the plan. It is inevitable that you will hit a losing streak at some point, and this could mean you are betting at levels you aren’t used to, but the strategy requires it. The whole point of using a system such as D’Alembert is to add structure to your bets and eliminate emotional betting, so deviating from the plan could lead to further issues.

Limit your betting time – Playing anything for a long time that requires you to concentrate and perform a specific action on every outcome can be tiring. The longer you play, the more likely that you will make mistakes. Plus, the house edge will always sneak up on you at some point. It’s therefore a good idea to set a time limit.

Does The D’Alembert Betting System Work?

If you want a betting system that will guarantee profits, then no, the D’Alembert strategy will not work.

Ultimately, the whole strategy is based on a myth. If a coin lands on heads on the first toss, it is not more probable that tails will land on the second toss. Both outcomes have the same 50/50 chance.

This is gambler's fallacy and it forms the backbone of the D’Alembert system.

Increasing and decreasing your bet size based on the probability of the next outcome is illogical as no one can predict the next outcome of a 50/50 bet.

Casinos know that players look for patterns and the D’Alembert system is a classic example of pattern play. They will openly allow these strategies to be played because they know it gives the player no overall advantage.

That doesn’t mean there aren’t some positive factors in using the D’Alembert strategy though.

The overall aim of the D’Alembert is to grind out small wins while keeping losses to a minimum and in many scenarios it does that. It’s just not guaranteed.

The system can also help to manage bankroll and provide some betting structure for players who need it. By placing controlled bets, with measured stakes, it can help to feel a little more in control of the situation.

The only guaranteed way to gain an advantage over casinos and bookmakers is with strategies such as value betting or placing matched bets.

These are mathematical strategies that look at the actual value and expected returns of each bet which means you only place bets that give you the edge over the casino.

Value betting can apply to both sports betting and casino play and it uses a range of tools, calculators and strategies to make sure the player gets as much value as possible out of each bet.

Alternatives To The D’Alembert Betting System

The D’Alembert strategy is probably the second most used betting system behind the infamous Martingale system. There are others, however, all of which have their own pros and cons, here’s a quick summary of the main ones.

Martingale Strategy – a negative progressive system that is more aggressive than D’Alembert’s. Rather than moving up and down in units, you double your stake after a loss and revert to the original stake after a win. You need a good sized bankroll to play the Martingale system as bet sizes can get hefty when you keep doubling up. This can also lead to issues if there is a maximum bet limit as it can mean you can’t place a bet high enough to recoup losses. To find out more about the Martingale Strategy, read our guide here.

Paroli system - this is a positive progressive strategy that is the opposite of Martingale. With Paroli, you double your stake after every win until you hit three consecutive wins and then you drop down to your original stake. You also drop to the original stake after a loss. This system helps to maximise winning streaks but can also leave you vulnerable to losing streaks. To find out more about the Paroli system, take a look at our guide.

Fibonacci system – if you’re already familiar with the Fibonacci sequence, then you might have a head start on this strategy. This betting system uses the well-known sequence (1, 1, 2, 3, 5, 8, 13 etc.) as a betting structure. You work your way up through the sequence increasing the bet size after every loss, and then reverse two steps after a win. The system has its merits but can get quite complex when playing in real time without a pen and paper.

Labouchere system – if you thought the Fibonacci system was complicated, it has nothing on the Labouchere system! You start by setting your own sequence of numbers that represent betting stakes. Your first bet is the sum of the first and last numbers in the sequence. After a win, you cross out those numbers and move onto the new first and last numbers; after a loss, you add the value of the lost bet to the end of the sequence and start again. This requires strong mental agility and concentration to implement well.

Keep Gambling Fun

Whether you decide to implement a strategy or not when gambling, the important thing to remember is to always keep it fun.

Setting your own time limits or a profit/loss limit can help to keep your betting levels under control. If you feel you need some support, there are lots of resources available. You can contact GAMstop for further professional advice and information.