How it works
Pick a base bet (say 1 unit = $100). After every loss, increase the next bet by one unit. After every win, decrease it by one unit (never below the base). When your wins and losses for the cycle even out, you’re ahead by one unit per win — then you reset.
| Situation | Next bet | Logic |
|---|---|---|
| Loss at 3 units | 4 units | One step up the ladder |
| Win at 4 units | 3 units | One step down |
| Win at the base (1 unit) | 1 unit | Stay — never below base |
A worked example
1 unit = $100 on Banker. A rough patch, then recovery:
Two losses, two wins — yet you finish +2 units, because the wins landed on bigger stakes than the early losses. That’s the D’Alembert’s party trick: equal win/loss counts at the right moments leave you ahead.
The honest math
The trick has a price. The system assumes results drift toward balance, but streaks don’t care: ten Banker losses in a row (it happens) walks your bet up to 11 units with 55 units already spent. And because Banker wins slightly more often than it loses, the ladder spends more time climbing after losses at exactly the moments your stake is biggest. The 1.06% edge applies to every rung.
When to use it
- When you want mild variance shaping without doubling anything — the calmest of the classic progressions.
- With a ladder cap: the bro stops at 6 units, full stop.
- On Banker, units at 1–2% of bankroll, session limits set per the bankroll guide.
Pros & cons
What the bro likes
- Slowest stake growth of any classic progression
- Easy to run — one unit up, one unit down
- Equal wins & losses mid-cycle leave you ahead
- Small bets most of the time
What to watch
- Built on the gambler’s fallacy — outcomes never “balance” on schedule
- Long slides recover one unit at a time
- Cold shoes still cost real money (55 units per 10-loss run)
- House edge unchanged: 1.06% of everything wagered
How it compares
| This system | The 1-3-2-6 | The Martingale | |
|---|---|---|---|
| Type | Negative progression | Positive progression | Negative progression |
| Stake growth | +1 unit per loss | Fixed ladder on wins | Doubles per loss |
| Recovery speed | Slow — one unit per win | Instant reset | One win (if you survive) |
| Guide | You’re here | Read → | Read → |
Quick questions
Is the D’Alembert low risk?
Lower-octane, not low-risk. Stakes grow arithmetically instead of geometrically, so disasters arrive slower — but a long cold run still stacks losses you then recover one unit at a time.
Why is it named after a mathematician?
Jean le Rond d’Alembert argued (wrongly) that past outcomes make opposite results more likely — the equilibrium fallacy. The system inherits both his name and his error.
Best base unit for the D’Alembert?
Small enough that base × 10 fits your session bankroll comfortably — in practice 1% of bankroll, so a ladder-top bet stays survivable.