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Roulette Strategy Simulator

Run Martingale, D'Alembert, Fibonacci, Paroli or Labouchère over many sessions, watch what happens.

This page compares systems against each other on the same wheel: the spread of outcomes a staking pattern produces on even-money roulette bets, a question about variance and about how much you stake, never about whether a pattern can turn a negative-expectation game positive. To take one system apart on its own, spin by spin against a bet size and table limit you choose, the Martingale simulator runs Martingale in depth.

The bars are the first six bets of a losing run, in units, on one scale. Paroli is the exception: it raises after a win, so its six are a winning run.

2. Watch one session

    Bankroll

    $500

    Martingale, 200 spins planned

    Next bet$5

    of a $500 table limit

    Example session at these settings, fixed draw

    The session bets red on every spin. Press Run to play one.

    3. Set the table

    Across 5,000 sessions

    Simulating 5,000 sessions…

    All six, same settings

    Same edge on every spin. About 4.6x apart in what crosses the table.

    SystemTurnover / sessionExpected costAverage result
    $1000-$27-$29
    $1689-$46-$49
    $1869-$51-$56
    $1911-$52-$53
    $4319-$117-$124
    $4640-$125-$135

    European wheel, $500 bankroll, $5 unit, $500 table limit, 200 spins, 5,000 sessions each. Ordered by how much money crosses the table. Expected cost is turnover times the wheel edge, exactly 2.70% of every dollar staked on every row by construction. Average result is what this 5,000-session sample actually did, which lands near that rate rather than on it, because a sample of a skewed distribution is not the whole of it.

    Turnover runs from $1000 to $4640, about 4.6x, with no system being a worse bet than any other on any individual spin. Every row above costs on average: what changes between systems is how much crosses the table, never the rate applied to it.

    Win rate against session length

    Martingale’s win rate falls as the session gets longer

    0%20%40%60%80%77%45%25 spins49%36%100 spins31%33%200 spins

    MartingaleFlat bettingshare of sessions that finish in profit

    Sessions in profit, not sessions ahead by any particular amount. Martingale starts far ahead on this measure and gives it back: 31% by 200 spins is below flat betting’s 33%, not because the bet changed but because every extra spin is another chance to meet the losing run that gives back every small win at once.

    Same opening settings as the table, each point averaged across 20 seeds rather than the single seed elsewhere on this page, because the 200-spin gap is narrow enough that one seed is not enough to call it honestly.

    Share this scenario

    A link to this page opens the simulator on the same system, wheel, bankroll, base unit, table limit and session length shown here. It carries those inputs and nothing else: nothing is stored, and nothing in it identifies you.

    Written and reviewed by Alexander Korsager · last reviewed September 26, 2026 · corrections

    The idea

    What this tool shows

    Every roulette betting system is a way of arranging your bets over time. Martingale doubles after a loss to recover in one hit; D'Alembert nudges the stake up one unit after a loss and down one after a win; Fibonacci walks up its sequence on losses; Paroli presses winners instead of losers; Labouchère crosses numbers off a list until the list is empty. They feel different, and their bankroll curves look different.

    1. None of them changes the house edge.Wheels do: a single-zero wheel pays every even-money bet 18 times in 37 and takes it 19, a 2.70% edge; a double-zero wheel is 5.26%; and a third layout that debuted at the Venetian in 2016 as Sands Roulette and has since spread to other Las Vegas floors, the triple-zero wheel, costs 7.69% on every bet on it, the priciest of the three. A half-back rule can still beat the pocket count on six bets, and the two names are not interchangeable: la partage, on a single-zero wheel, returns half your stake when it lands on the single zero; surrender, on a double-zero wheel, does the same across both zeros, cutting that table to 2.63%, cheaper than a plain single-zero wheel's 2.70%. This simulator doesn't model either rule or the triple-zero wheel; the Roulette Payouts tool prices all three. The 2.70% single-zero figure this page runs on is a rate, though, not a bill. It is 2.70% of every dollar you put on the table, and what a system changes is how many dollars that is.

    2. The gap is larger than the phrase "same edge" makes it sound.Running each system 5,000 times at this page's opening settings (European wheel, $500 bankroll, $5 unit, $500 table limit, 200 spins) and reading off how much each one turns over, the comparison table above the controls shows every system side by side, ordered by turnover so the size of the gap is the visible fact rather than something you have to remember across six separate runs. Multiply any row's turnover by the wheel edge and you get that row's expected cost, with no system being a worse bet than any other on any individual spin.

    3. This simulator runs your chosen system thousands of times with the parameters you set and reports the distribution: how often the bankroll is wiped out before the session ends, where the median session finishes, and how wide the best and worst cases are. The panel prints your average turnover next to the wheel edge, so you can do that multiplication yourself on whatever settings you choose. Run a single session too, and watch the curve build.

    FAQ

    Questions players ask

    Which roulette system is best?

    None of them improves the rate: every even-money bet on a single-zero wheel costs 2.70% of what is on it, whatever pattern put it there. They are not equally expensive, though, and the usual answer stops one step too early. Because each system stakes a different amount to play the same 200 spins, the expected cost of a session at this page's opening settings varies several-fold across the six, from flat betting at the cheap end to Labouchère at the dear one; the comparison table on this page has the exact figures. If the question is which one loses the least money, the answer is the one that turns over the least, which is flat betting.

    Which system loses the least money?

    Flat betting, and by a wide margin, because expected loss is turnover times the wheel edge and flat betting has the lowest turnover of the six. The comparison table on this page runs all six over 5,000 sessions each at the opening settings and orders them by turnover, so the size of the gap between flat betting and Labouchère (the dearest of the six) is a row you can read rather than a set of figures to remember. The ordering is stable across seeds. It is not stable across settings: give an escalating system a deeper bankroll or a higher table limit and it stakes far more before anything stops it, which widens the gap rather than closing it. Labouchère's place at the expensive end also rests on a stopping rule this page does not use. It rewrites the crossed-off line and plays your full spin count, where the system is usually taught to finish the moment the line clears; stop there and it stakes about $354 rather than the several thousand it reaches by playing on. That is a shorter evening rather than a cheaper way to bet, though, because it ends after about seven spins instead of 200. The rate is 2.70% either way, and the methodology note below has the figures.

    Why does Martingale bust so often in the simulator?

    Six consecutive losses end it at the opening settings, and it is your bankroll rather than the table limit that does the ending. The progression is 5, 10, 20, 40, 80, 160, so six losses have taken $315 and leave $185, and the seventh bet asks for $320. The $500 table limit would not have refused anything until the eighth bet at $640, so the received idea that Martingale dies at the table limit is not what happens at an ordinary bankroll. Six losses in a row is (19/37) to the sixth power, or 1.83% per attempt, which over a few hundred spins comes up far more often than people expect, and when it lands it gives back every prior small win at once.

    Does Martingale really win most sessions?

    It depends entirely on how long you sit there, and the simulator will show you the crossover. Over 25 spins at the opening settings about 77% of Martingale sessions finish in profit against 45% flat. By 100 spins it is 49% against 36%, and by 200 spins the ordering has inverted: 31% against 33%. Every extra spin is another chance to meet the six-loss run, and one of those gives back every small win at once. The high win rate is real and it is temporary, which is a different thing from an edge.

    Can any staking plan beat roulette?

    No. As long as each individual spin is negative expectation, every finite combination of those spins is also negative expectation. Only a biased wheel or dealer signature (not a staking pattern) can change that.

    Methodology

    How this is calculated

    Nothing here is a formula for what a system returns, because there is no closed form once a session can end early. Every figure comes out of playing sessions.

    One session places a single even-money bet per spin, at the stake the chosen system's rule asks for next, until it reaches your spin count or meets a stake it cannot place.

    That refusal is checked before the wheel turns, against the table limit and against what is left of the bankroll, and a stake that fails either check ends the session rather than being placed smaller.

    Those two things are the only ways a session ends here, which matters most on Labouchère: a line that has been crossed off is rewritten and play continues, rather than the run finishing on the target the line represents. The note under Limits prices that choice, because it is most of what the Labouchère figures on this page are.

    The panel above the histogram is 5,000 such sessions, drawn from one seeded generator so that a given seed reproduces the whole sweep exactly and Re-run draws a fresh one. The wheel control changes exactly one number, the chance of winning a spin: 18 pockets in 37 single-zero, 18 in 38 double-zero.

    The edge printed beside your results is computed from that same probability as 1 minus twice it, rather than being typed in as 2.70%, so it cannot describe a probability the sweep is no longer using.

    Common misreadings5
    • A high session win rate is not an edge, and this page is built to show you the difference. Over 25 spins about 77% of Martingale sessions finish in profit; by 200 spins that is 31%, below flat betting's 33%. Nothing about the bet changed. The win rate was borrowed from sessions that had not yet met the losing run, and every extra spin is another chance to meet it.
    • The median and the average are far apart on four of the six systems, and they answer different questions. At the opening settings Labouchère's median session ends at $120 while its average ends at $365, because a small minority of sessions finish very high. The median is what a typical night looks like; the average is what the pattern costs you if you keep coming back. Reading either as the other is the single easiest mistake to make on this panel.
    • Flat betting has the narrowest spread of the six here, not the widest. Its ending bankrolls have a standard deviation of about $72 against $138 to $587 for the others, a full range of $620 against up to $2,350, and a middle-half range of $100 against up to $805. The systems that feel like they smooth the ride are the ones generating the fat tails, which is the same fact the bust rate reports from the other direction.
    • Pressing Re-run until the figures look kinder is drawing another sample of the same distribution, not finding a different answer. The seed changes; the model does not.
    • Losing less is not winning. Flat betting is the cheapest pattern on this page and its average session still ends below where it started, on both wheels, at every setting the controls reach. The ordering here is between costs, and there is no free option in it.
    Assumptions6
    • Every spin is independent and the wheel is fair. No bias, no dealer signature, no tracking, which is also the only route by which any of this changes and the reason the answer to whether a staking plan can win is no.
    • One even-money bet per spin, at the stake the system asks for. Red, black, odd, even, high and low all behave identically here, and nothing on this page models the inside bets, which have the same edge on a single-zero wheel and a much wider spread.
    • The systems are implemented as they are conventionally taught. Martingale doubles after a loss and resets on a win. D'Alembert moves one unit up on a loss and one down on a win, never below one. Fibonacci steps one place up the sequence on a loss and two back on a win, along a sequence that stops growing at its sixteenth entry of 987 units. That clamp is far out of reach at the opening settings and it is not out of reach everywhere, because neither the bankroll nor the table limit field has a maximum: from roughly a $20,000 bankroll with a matching limit it starts to bind, and a stake pinned at 987 units is no longer the system. Paroli doubles after a win and banks after three, resetting on any loss. Labouchère stakes the two ends of a line, crosses both off on a win and appends the stake on a loss, starting from 1-2-3-4, which is the standard teaching line rather than a figure derived from anything. When that line is crossed off a fresh 1-2-3-4 is written and the session continues, which is a decision about when to stand up rather than a detail of the rule. See the note under Limits.
    • A refused stake ends the session. Real players facing a stake they cannot cover usually bet what they have left instead, which continues the session at a broken progression. Modeling the refusal is the conservative choice for the bust rate and it understates turnover, so the cost figures here are if anything the low end.
    • Your bankroll is what you brought and there is no reload. The table limit is a maximum on your own bet, and real even-money maximums are usually far above the inside-bet maximum quoted for a table.
    • Stakes are exact multiples of your unit with no minimum bet and no rounding to chip denominations, which lets a progression place $315 across six bets in a room that would round some of them.
    Limits7
    • The identity underneath all of it is Wald's: average end equals your bankroll minus average turnover times the wheel edge. It holds for every system, at every setting, however a session ends, because each bet's expected result is minus the edge times whatever is on it and the decision to place it was made before the wheel turned. Everything the page argues follows from that one line, and math.test.ts asserts it exactly on a fully enumerated 12-spin distribution rather than approximately on the sample.
    • 5,000 sessions is a sample of a very skewed distribution, not the distribution. Bust rate and median settle quickly; the mean does not, because it is carried by a small number of extreme sessions. Labouchère is the worst case here: across twenty seeds at the opening settings its best session in each sweep landed between $2,325 and $2,540 on a $500 bankroll, and its printed average moved by up to $30 from seed to seed while its median moved by about $10.
    • The turnover multiples quoted on this page belong to the systems at these settings, not to the systems. What an escalating system stakes is capped by whichever of your bankroll and table limit stops it first, so the multiple moves a long way with the controls: D'Alembert turns over about 4.4 times what flat betting does at the opening settings, about 8.5 times on a $2,000 bankroll with a $1,000 limit, and about 2.6 times if you raise the unit to $10 on the same $500, because it then busts sooner. Busting early is the thing limiting what these systems cost you.
    • Crossing the line off is where Labouchère is usually taught to stop, and this page does not stop there. The line's sum is the system's target, so a session that clears it is up exactly that much: 1-2-3-4 at a $5 unit is $50, and across 200,000 sessions measured on 2026-09-10 all 174,475 that cleared the line ended on exactly $550, without a single exception. This simulator writes a fresh line and plays your full spin count instead, because the other five systems have no natural finish and a system that stops on a win cannot be set beside five that do not. The two readings are nothing like each other. Stopping at the first clearance stakes about $354 over about seven spins and finishes ahead 87.2% of the time, and the 12.8% that never get there leave a median of $80. Playing on stakes about $4,709 over about 82 spins, clears the line a median of six times, and busts 84.0% of the time. Wald's identity holds on both and is the whole of the difference: $354.40 staked costs $9.90 against a predicted $9.58, and $4,708.80 staked costs $126.52 against a predicted $127.26. That 87.2% is this page's warning about Martingale arriving through a different door, because it is bought by standing up sooner and not by a better bet.
    • Bust here means the next stake could not be placed, not that the bankroll reached zero. Busted Martingale sessions at the opening settings stop holding a median of about $220, spread across everything from nothing to $425, because where a losing run starts decides what a doubling progression leaves stranded.
    • The histogram bins between the worst and best session actually seen, so its bars are equal in width and not in probability, and its ends move when the sample does. It is a picture of the shape rather than a table to read values off.
    • There is no clock and no venue in this. 200 spins is a couple of hours at a busy live table and a great deal less online, and nothing here counts drinks, tips, travel or the value of the time.
    Evidence

    Everything is computed by math.ts, and math.test.ts covers it three ways that fail differently. The staking rules are checked against a hand-written run of twelve spins and against closed forms over every possible history of twelve spins, so a misread rule breaks the enumeration rather than passing quietly.

    The session loop is checked at the exact boundaries of both refusal conditions, including a stake landing precisely on the table limit and precisely on the remaining bankroll.

    Wald's identity is asserted exactly on a fully enumerated distribution for all six systems at four win probabilities, and on the sweep at the shipped defaults on both wheels, together with the consequence this page leads on: loss divided by turnover is the wheel's edge for all six, while the amounts lost differ several-fold.

    The Martingale bust point quoted above is pinned directly, six spins played and $315 staked leaving $185. The house edges are derived from the win probability rather than tabulated, and checked against the published 2.70% and 5.26%.

    The Labouchère stopping-rule figures come from playing the shipped stakeUnits and advance under both stopping choices, 200,000 sessions each at the opening settings on 2026-09-10, and math.test.ts pins them, including that a cleared line ends exactly one line sum up and that Wald holds on each.

    The turnover, median, mean and spread figures quoted in this block are SYSTEM_COMPARISON's own fields (#1067 extended it to carry them), computed once at module load rather than typed in from a one-off run, and the FAQ's and misuse block's Martingale-versus-flat crossover reads MARTINGALE_VS_FLAT_CROSSOVER, itself an average across 20 seeds per spin count rather than one seed's sample, because the 200-spin gap is narrow. math.test.ts pins the count of systems with a wide median-mean gap, the ranking of flat's spread against the rest, and the crossover's ordering at each spin count; a passing test means the simulation implements this model correctly, not that any particular table matches it.

    Two things in the intro are not arithmetic and are sourced separately from the tests above.

    That a half-back rule exists, that it is called la partage on a single-zero wheel and surrender on a double-zero one, and that it reaches the six even-money bets only, come from wizardofodds.com's roulette basics page and casinonewsdaily.com's surrender-rule guide, both retrieved 2026-09-10.

    That a triple-zero wheel exists, carries 39 pockets and debuted at the Venetian in 2016 as Sands Roulette come from wizardofodds.com's roulette basics page and americancasinoguidebook.com's triple-zero guide, both retrieved 2026-09-11; its 7.69% edge is arithmetic like the other two and is derived here, not transcribed.

    Gambling can cause serious harm. The National Problem Gambling Helpline is free, confidential and open 24/7, call or text 1-800-MY-RESET (1-800-697-3738), or chat at ncpgambling.org/chat.

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