Martingale Roulette: We Simulated 1,000,000 Spins
Martingale is the oldest betting system in roulette, and the most convincing to watch. Lose a few spins in a row, double the bet, and the first win doesn't just recover the losses, it puts one base unit ahead. It feels like a rule you found in the math instead of a rule the casino already priced around. Here's what actually happens across roughly one million simulated spins of it.
What Martingale is
- Start with a base wager on red or black.
- After every loss, double the next bet.
- After a win, drop back to the base bet.
- The theory: one eventual win recovers every previous loss in the streak, plus one base unit of profit.
The system says nothing about which spin wins. It only changes how much is riding on the spin that eventually does.
The math it's fighting
We simulated American roulette, 38 pockets: 18 red, 18 black, and 0 and 00 both green. Betting red wins 1:1 on 18 of those 38 pockets, a 5.26% house edge on every spin regardless of bet size. No betting pattern changes that number. Martingale doesn't fight the house edge, it fights the shape of how that edge gets paid out.
Methodology
24,700 sessions, seed 43, each session up to 50 spins. Base wager $5 on red, starting bankroll $500 per session, table limit $500. A win pays even money and resets the next bet to $5. A loss doubles the next bet, capped at the $500 table limit. A session ends either at 50 spins or the moment the bankroll can't cover the next required bet, whichever comes first — that second case is counted as a bust. Every number below is the simulation's actual printed output.
Results
| Metric | Value |
|---|---|
| Sessions run | 24,700 |
| Total spins actually played | 999,551 |
| Total amount wagered | $16,205,915 |
| Net result | -$876,985 |
| ROI | -5.41% |
| Profitable sessions | 59.5% |
| Busted sessions (bankroll couldn't cover the next bet) | 38.6% |
| Sessions that ended negative but not busted | 2.0% |
| Longest losing streak observed | 7 spins |
| Largest single wager ever placed | $320 |
| Bets actually placed at the $500 table limit | 0 |
| Median session result | +$95 |
| Best session result | +$190 |
| Worst session result | -$500 (full bankroll) |
The table limit almost never mattered
The $500 table limit was set to be a realistic cap, but it turned out to be the wrong constraint to worry about. Doubling seven times in a row from a $5 base needs $640 to cover the next bet — past the table limit on its own. But a $500 bankroll runs out well before that: five straight losses already cost $155, six cost $315, and the seventh bet would need $320 with only $185 left to cover it. On this bankroll, the bust always came from running out of money, not from hitting the table's ceiling. The largest wager ever actually placed across 999,551 spins was $320, and the $500 cap was never once the reason a bet got capped in practice.
Martingale vs. flat betting
Same seed, same 999,551 spins, flat $5 on red every time, no doubling:
| Martingale | Flat $5 | |
|---|---|---|
| Total wagered | $16,205,915 | $4,997,755 |
| Net result | -$876,985 | -$271,605 |
| ROI | -5.41% | -5.43% |
The ROI numbers land within a rounding error of each other, and both sit close to the 5.26% house edge itself. That's the entire finding: Martingale loses about the same fraction of every dollar wagered as flat betting does. It just wagers far more total dollars to get there, because every losing streak gets re-bet at escalating size instead of a flat $5. More money moving through the same house edge produces a bigger dollar loss, not a smaller one.
Why it looks like it's working
59.5% of sessions in this simulation ended positive, most of them for a modest +$95, a handful of small wins stacked from short losing streaks that recovered on schedule. That's the version of Martingale most players actually see, because most sessions are short and most losing streaks are short too. The other side of the same coin is the 38.6% of sessions that busted the entire $500 bankroll, one long streak deep enough that the required bet outran the money left to cover it. Martingale doesn't trade a small chance of a small loss for a small chance of a small win. It trades a large chance of a small win for a smaller chance of losing the entire stake in one streak. Both sides average out to the same house edge; the system just moves the losses from "small and frequent" to "rare and total."
The takeaway
Martingale changes the distribution of wins and losses. It does not remove roulette's house edge. Every dollar run through it is still worth 5.26% less than the dollar the casino started with, on average, whether it's wagered $5 at a time or $320 at a time. The system just repackages that same cost into a lot of small winning sessions and a smaller number of sessions that lose the whole bankroll at once, which is a worse shape to be exposed to, not a better one, if going bust is the outcome you're actually trying to avoid.
See how every roulette bet's odds and payouts actually work, why the American wheel costs more than the European one, or try flat betting, Martingale, or anything else yourself on the free roulette wheel, no bankroll required.