D'Alembert
A slow progression that adds one unit after a loss and subtracts one after a win.
- Roulette type
- best tested on European or French roulette
- Bet focus
- even-money outside bets: red/black, odd/even, low/high
How The Strategy Works
This guide expands the short strategy summary into a practical simulator workflow. Use it to understand the betting sequence, bankroll pressure, and failure points before risking real money.
The exact numbers can be changed, but the test should keep one fixed base unit, one roulette variant, and one stopping rule so the result remains readable.
Practical Betting Example
- 1Choose one clear bet type and one base unit.
- 2Run the first spin with the planned stake.
- 3Apply the strategy rule after a win or loss.
- 4Reset, reduce, or stop exactly where the rule says.
- 5Record the result before starting the next cycle.
Bankroll And Risk Rules
- Set a maximum session loss before the first spin.
- Track maximum drawdown, maximum stake, and total cost per cycle.
- Compare European, French, and American roulette separately.
- Never judge the system from a small lucky sample.
Common Mistakes
- Changing the rule after emotional wins or losses.
- Ignoring zero and double-zero outcomes.
- Tracking hit rate without tracking net profit.
- Increasing the base unit before the strategy is tested over a long sample.
Simulator Checklist
- Run at least 500 simulated spins.
- Repeat the same test with a different roulette variant.
- Write down the largest losing streak and largest stake.
- Compare the result with flat betting.
Key Features
- Increase by one unit after a loss.
- Decrease by one unit after a win.
- Usually played on outside bets.
How This Strategy Was Created
It is linked to Jean le Rond d'Alembert and the old equilibrium idea that wins and losses should balance over time.
Why This Option Is Useful
It is good for conservative simulations because bet sizes change slowly and drawdown is easier to read.
How To Test It In The Simulator
- Compare European and American wheels.
- Track average bet size.
- Test stop-win and stop-loss boundaries.
Important Risk Note
No roulette strategy removes the house edge. Use this page for education, bankroll planning, and simulated testing only.
Choose An Online Roulette Simulator
Choose the roulette model you want to test with this strategy.
European Roulette
EuropeanSingle-zero wheel for lower house edge testing and clean baseline simulations.
- House edge
- 2.70%
- Numbers count
- 37
American Roulette
AmericanDouble-zero model for comparing volatility, drawdown, and bankroll pressure.
- House edge
- 5.26%
- Numbers count
- 38
French Roulette
FrenchSingle-zero rules with La Partage context for even-money strategy analysis.
- House edge
- 1.35%*
- Numbers count
- 37
What To Test Next
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