D’Alembert Betting Strategy for Roulette, Blackjack, Baccarat & Crash
The D’Alembert system is a popular betting strategy named after the 18th-century French mathematician Jean le Rond d’Alembert. It is based on the “equilibrium of nature” theory—the idea that over time, wins and losses will eventually balance out.
Unlike the aggressive Martingale system, the D’Alembert is considered a low-variance or “conservative” progression strategy.
How It Works
The system follows a simple “Add one on a loss, subtract one on a win” logic. It is designed for even-money bets (where you have roughly a 50% chance of winning).
1. Define Your Base Unit
First, you decide on a “unit” of currency (e.g., $5, $10, or $1). This unit will be the amount you increase or decrease your bet by.
2. Start with One Unit
Place your first bet using one unit.
3. The Rules of Progression
After a Loss: Increase your next bet by one unit. After a Win: Decrease your next bet by one unit. (If you win with a single unit, your next bet remains at one unit).
Example Scenario ($10 Unit)
| Round | Bet Amount | Result | Profit/Loss |
|---|---|---|---|
| 1 | $10 | Loss | -$10 |
| 2 | $20 | Loss | -$30 |
| 3 | $30 | Win | -$0 |
| 4 | $20 | Win | +$20 |
| 5 | $10 | Loss | +$10 |
As shown above, the goal is that once you have an equal number of wins and losses, you will be in the profit by the number of units equal to the number of wins.
The Mathematical Theory
The strategy relies on the Law of Equilibrium. D’Alembert believed that if a coin lands on heads, it becomes more likely to land on tails next time to maintain balance.
Best Games for This Strategy
The D’Alembert system only functions logically on bets that offer close to a 1:1 payout (even money).
- Roulette: Betting on Red/Black, Even/Odd, or 1-18/19-36.
- Baccarat: Betting on the Player or the Banker (though Banker bets often have a small commission).
- Blackjack: Since most hands pay 1:1, though “doubling down” or “splitting” can complicate the unit progression.
- Craps: Betting on the Pass/Don’t Pass line.
Pros and Cons
Pros
Unlike the Martingale (where bets double), your stakes rise linearly ($10, $20, $30…). You are less likely to hit table limits or go bust quickly. You don’t need a calculator; you just add or subtract a single unit.
Cons
If you hit a long losing streak, it takes a long time to claw back your losses because the bet size decreases as soon as you start winning.
Applying the D’Alembert strategy to Crash games
Applying the D’Alembert strategy to Crash games (like Aviator or JetX) is common, but it works differently than in traditional casino games because you have to dictate your own “even money” odds.
In Roulette, the game defines the 1:1 payout. In Crash, you must create it by setting an Auto Cashout at 2.00x.
How to Apply It
To treat a Crash game like a D’Alembert sequence, you follow these steps:
- Set Auto-Cashout to 2.00x. This ensures that every win pays exactly double your stake (a 1:1 profit), mimicking a Red/Black bet in Roulette.
- Pick a Base Unit. For example, $1.
- The Loop.
- Lose (Crash before 2.00x): Increase your next bet by $1.
- Win (Reach 2.00x): Decrease your next bet by $1.
Is it effective for Crash?
Compared to the Martingale (doubling your bet), the D’Alembert is much “safer” for Crash. If you lose five rounds in a row starting at $1, your next bet is only $6. Under Martingale, your next bet would be $32.
Also you should note that the D’Alembert requires discipline. In Crash, it is very tempting to “chase” a high multiplier (like 10x or 50x) when you see it happen. If you deviate from the 2.00x cashout, the D’Alembert math breaks, and you risk losing the balance the system is trying to create.
And most importantly, for the strategy to be effective, always look for the right opportunity – for example, 1x several times in a row – and only then start placing bets.
Summary Table for Crash
| Feature | D’Alembert Approach |
|---|---|
| Risk Level | Medium-Low |
| Exit Point | Strict 2.00x Auto-Cashout |
| Progression | Linear (+1 / -1) |
Automation Script for Crash
This script implements the D’Alembert betting logic and allows you to set your base wager and target payout through the UI on Nanogames and BC.Games. Take a look at our guide to betting scripts to find out more.
var config = {
unit: { value: 1, type: "number", label: "Base Unit" },
payout: { value: 2, type: "number", label: "Payout (2.0 recommended)" },
};
// State variables
let nextBet;
let isFirstGame = true;
function main() {
nextBet = config.unit.value;
log.info("D’Alembert Automated: Unit is " + nextBet);
game.onBet = function () {
log.info("Game Starting... placing bet of " + nextBet);
game
.bet(nextBet, config.payout.value)
.then(function (payout) {
if (payout > 0) {
log.success("Win! Result: " + payout + "x");
nextBet = Math.max(config.unit.value, nextBet - config.unit.value);
} else {
log.error("Loss. Increasing stake.");
nextBet = nextBet + config.unit.value;
}
log.info("Next round will bet: " + nextBet);
})
.catch(function (err) {
log.error("Betting Error: " + err);
game.stop();
});
};
}Ensure your Payout in the UI is set to 2. If it’s set to something like 1.1 or 10, the D’Alembert math (linear +1/-1) won’t work correctly because the wins won’t balance the losses.
As you can see, using D’Alembert in Crash is one of the more “stable” ways to play. It is a tool for bankroll management, but not a guaranteed way to win.
Always use a mix of different strategies and remember that the most important thing is to cash out at the right time and collect your winnings.
