Fibonacci vs D'Alembert
Which roulette betting strategy is right for you? Compare these two popular systems side-by-side.
Fibonacci Strategy
Follow the Fibonacci sequence for bet sizing, moving forward after losses and back after wins.
D'Alembert Strategy
Increase bet by one unit after a loss, decrease by one after a win.
10,000 Simulated Sessions Each: Fibonacci vs D'Alembert
We ran both systems through 10,000 simulated sessions on a European wheel under identical conditions: $1,000 bankroll, stopping at $1,500 (win), $500 (loss), or 500 spins.
| Measured over 10,000 sessions | Fibonacci | D'Alembert |
|---|---|---|
| Sessions ended in profit | 48.9% | 36.6% |
| Average session result | −$135 | −$155 |
| Average spins per session | 341 | 163 |
| Average worst drawdown | −$444 | −$413 |
| Best single session | $500 | $565 |
| Worst single session | −$940 | −$610 |
| Hit the table limit | 0% | — |
In this run, Fibonacci came out ahead on both measures — more sessions in profit and a smaller average loss. The house edge still won overall: both averaged a losing session.
How Fibonacci sessions ended
How D'Alembert sessions ended
Methodology: fixed-seed runs from our open simulation engine, using the same settings as the strategy guides and interactive simulators — the numbers here match each system's guide page and can be reproduced there. Both systems lose on average because no betting progression changes the house edge; the comparison shows how differently they get there.
Side-by-Side Comparison
| Feature | Fibonacci | D'Alembert |
|---|---|---|
| Style | aggressive | moderate |
| Complexity | moderate | simple |
| Progression Type | negative | negative |
| Best For | Moderate sessions | Conservative players |
Fibonacci
Pros
- ✓Slower progression than Martingale
- ✓Based on famous mathematical sequence
- ✓More sustainable for longer sessions
Cons
- ✗Still leads to large bets over time
- ✗More complex to remember
- ✗Cannot overcome house edge
D'Alembert
Pros
- ✓Very slow and safe progression
- ✓Easy to understand
- ✓Lower variance than Martingale
Cons
- ✗Takes longer to recover losses
- ✗Still cannot beat house edge
- ✗Profit potential is limited
Quick Summary
Quick Simulation: Fibonacci on Red
Starting balance: $1,000 | Base bet: $10 | European roulette odds
Quick Simulation: D'Alembert on Red
Starting balance: $1,000 | Base bet: $10 | European roulette odds