Like most online roulette systems, the D'Alembert is a roulette betting pattern that can be applied to all parts of the table. However, it is most suitable for even money bets (red/black, odd/even, low/high(, like the Martingale roulette system.
Despite its shortcomings, is a popular betting pattern, in its basic form and in its variants. It's based on a mathematical equilibrium theory devised by a the French mathematician named D'Alembert.
The progression this roulette system use is a very simple one: choose an amount as a starting bet (let's say 5), and if you lose, you add 1 unit to the next roulette bet; of you win decrease your next roulette bet by 1 unit. Continue the process until you're back to your starting unit size and you win, at which point you would be in profit by the size of your original wager.
In the above example, if you start by betting 5, this is what your progression could look like:
6 – win
5 – loss
6 – loss
7 – win
6 – win
5 – win
(your next bet should be 4, but being 5 your starting roulette bet, you can choose to start all over again by betting 5 units).
The biggest flaw in the D'Alembert roulette betting system is that the profit potential isn't very high, and if you have a few losses, you may find yourself in a bad position. Using the D'Alembert roulette betting pattern you need to get more wins than losses (i.e. The color you're betting on have to come out more often than the other... not likely to happen, if you look at the online roulette odds).
Another downside to the D'Alembert roulette system is that it doesn't take the zero into account, which can represent a disaster, especially if it comes out when the bet is high.
Our advice is never to use the D'Alembert betting system for too long.
There are some variations to the D'Alembert roulette betting pattern, particularly the Reverse D'Alembert, in which you raise your roulette bet size after a win, and decrease it after a loss. One thing to keep in mind with the Reverse D'Alembert roulette system is that you will need to start out with a higher betting unit, to ensure that if you start losing at the very beginning, you can actually decrease your bet (which you couldn't if your starting roulette bet would be 1 or 2 units).