A roulette system is a rule for adjusting your bet after a win or a loss. Every system on this page is a way of arranging stakes, and none of them alters the probability of a spin. That single fact, developed on the expected value page, is the thread that connects them all.
Martingale
The classic negative progression: double after every loss, reset after a win. It produces frequent small wins and rare large losses, and it is the system the whole site is built around, starting with the Martingale strategy guide.
Reverse Martingale
Also called anti-Martingale, this system doubles after wins instead of losses, pressing hot streaks and cutting losses quickly. Its risk profile is the mirror image of classic Martingale, as explained on the reverse Martingale page.
Fibonacci
A gentler negative progression that follows the Fibonacci sequence (1, 1, 2, 3, 5, 8...) after losses rather than doubling. It grows more slowly than Martingale but still faces the same limits, as the Martingale vs Fibonacci comparison shows.
D'Alembert
A mild negative progression that raises the bet by one unit after a loss and lowers it by one after a win. It is slower and flatter than Martingale, and it changes the bet by only one unit at a time.
Labouchere
A cancellation system that uses a written sequence of numbers to set stakes and crosses them off as bets win. It is more complex than doubling and is a more complex, sequence-based cancellation system.
Paroli
A positive progression that increases the bet after a win, usually for a fixed number of steps, then resets. It aims to ride winning runs while risking only a small base stake, and it is examined on the Martingale vs Paroli page.
Flat Betting
The baseline: the same bet every spin regardless of results. It has the lowest variance of any approach and is the cleanest reference for showing what progressions actually change, because it never changes the stake.
Positive Progression vs Negative Progression
Systems split into two families. Negative progression systems increase after losses (Martingale, Fibonacci, D'Alembert, Labouchere). Positive progression systems increase after wins (Reverse Martingale, Paroli). The two families have opposite risk shapes but the same long-run expectation.
Why No System Changes Expected Value
Because the house edge is baked into every bet through the zero pockets, rearranging stake sizes cannot make the average return positive. Systems change variance, session feel, and the shape of wins and losses, but never the edge. Any system can be studied honestly with the Martingale roulette calculator as long as that limit is kept in mind.