We Tested the Martingale System on 100,000 Sessions
The Martingale system, doubling your bet after every loss, won its target in 88.4% of our 100,000 simulated roulette sessions. It still lost money overall: the other 11.6% of sessions hit the table limit and lost about 4,870 chips each, wiping out the small wins and then some. The average session ended 124 chips down. No betting system can change the house edge; Martingale just hides it in rare, large losses.
How Martingale is supposed to work
- Bet 10 chips on red.
- If you win, take the 10 profit and start again at 10.
- If you lose, double: 20, then 40, 80, and so on.
- The first win recovers every loss in the streak and leaves you 10 chips up.
It seems impossible to lose. Red can't miss forever. And that's true, but it doesn't have to miss forever. It only has to miss long enough.
Our test
We simulated 100,000 sessions on a European wheel (18 red pockets out of 37) with these settings:
- Starting stack: 10,000 chips, what every new House21 player gets.
- Base bet: 10 chips on red, doubling after each loss.
- Goal: stop when 500 chips up.
- Table limit: 5,000 chips per spot, House21's actual limit.
For comparison, we ran 100,000 sessions betting a flat 10 chips on red, with the same goal, for up to 1,000 spins.
Results
| Martingale | Flat 10 chips | |
|---|---|---|
| Sessions that reached +500 | 88.4% | 2.3% |
| Sessions that hit the table limit | 11.6% | n/a |
| Typical (median) session | +500 | -280 |
| Worst session | -5,110 | -1,640 |
| Average session | -124 | -268 |
| Average spins per session | 97 | 992 |
Martingale reached its goal almost nine times in ten. That's exactly why it feels like it works: most people who try it a few times walk away winners. But one session in nine ended near -4,900, and over 100,000 sessions that wiped out every win and more.
The flat bettor lost more per session on average, but only because they played ten times as many spins. Per chip wagered, both lost the same 2.70%. The roughly 4,600 chips the average Martingale session put on the table, times the 2.70% edge, is the 124-chip loss.
Why the limit is hit so often
At a 10-chip base, the bets run 10, 20, 40, 80, 160, 320, 640, 1,280, 2,560. The next one, 5,120, is over the 5,000 limit. So nine losses in a row end the system, with 5,110 chips gone.
Nine reds missed in a row sounds rare, and per streak it is: about 1 in 400. But every losing bet starts a possible streak, and a session that runs a hundred spins gives it many chances. Over the whole test, one session in nine met it.
Even without a limit, your stack is a limit. Ten losses in a row would need 10,230 chips, more than you started with.
What Martingale really does
Every spin has the same 2.70% edge, whatever you bet. Changing the size of bets can't change the edge; it can only change the shape of your results. Martingale turns many small losses into many small wins plus a rare disaster. People remember the wins and blame the disaster on bad luck, which is why the system has survived since 18th-century France.
The same is true of every progression system: reverse Martingale, Fibonacci, d'Alembert, Labouchère. Each rearranges wins and losses. None removes the zero.
If you want to try it anyway
At House21 the chips are virtual, so it's a safe place to see it for yourself. Try it on our free roulette wheel with a fixed stop point, and notice how a long red drought feels when the bet in front of you is 2,560 chips.
If you play for real money anywhere, the lesson is simple: a system that "never loses" is one whose losses you haven't seen yet. Our bankroll guide and responsible gaming page have better ways to protect a stack.
How we ran the simulation
Each spin drew red with probability 18/37. A session ended at +500, at 1,000 spins, or when the next Martingale bet exceeded the 5,000 limit or the remaining chips. 100,000 sessions per strategy. You can read more about the history and math of the system on Wikipedia.