Odds & strategy math · Free tool
Martingale Strategy Calculator: How Long Your Bankroll Lasts
Quick answer
With a 100 USDT bankroll and a 1 USDT base bet, martingale can fund 6 losses in a row (1+2+4+8+16+32 = 63 USDT); the 7th bet of 64 is unaffordable. On red at a single-zero wheel, a run of 6 losses shows up in about 60% of 100-spin stretches. Our 50,000-session simulation lost 2.77 USDT per 100 wagered.
| Total lost after n losses | base × (2^n − 1) |
|---|---|
| 100 USDT bankroll, 1 USDT base | Covers 6 losses in a row |
| Reached +50 USDT (our simulation) | 48.67% of 50,000 sessions |
| Loss per 100 USDT wagered | 2.77 USDT, the same as flat betting |
| Does it beat the house edge? | No |
This martingale strategy calculator shows how many losses in a row your bankroll can pay for when you double after every loss, how often a streak that long turns up, and what happens across thousands of sessions. Set your bankroll, base bet, win chance and table limit. The streak figures update as you type, and the simulator runs up to 20,000 sessions in your browser.
With the defaults, the progression survives 6 losses. The 7th bet would be 64 USDT, but only 37 USDT is left, so the session stops with a 63 USDT loss.
How this is calculated
Martingale doubles the stake after each loss, so the bets in a losing run are base, 2 × base, 4 × base and so on. Their total is a geometric series:
total lost after n losses = base × (2^n − 1) next bet = base × 2^nThe progression can continue while the total stays within your bankroll and each bet stays within the table max.
The calculator finds the largest n that passes both checks. It then uses the exact losing-streak method from our chance calculator to find the probability of at least one run of n losses within 100 spins and within your session length. A run of that length doesn't always end a real session, because sessions that hit the profit target stop early, so the simulation is the better guide to how sessions actually end.
Worked example: 100 USDT bankroll, 1 USDT base, red on a single-zero wheel (48.65%).
- Bets in a losing run: 1, 2, 4, 8, 16, 32. Total = 1 × (2^6 − 1) = 63 USDT
- 7th bet = 1 × 2^6 = 64 USDT, more than the 37 USDT left: the progression ends
- Chance of losing one spin = 1 − 0.4865 = 0.5135; six in a row = 0.5135^6 ≈ 1.83%
- Each completed progression wins 1 USDT. You need 50 of them to reach +50
That last line explains the whole system. Each cycle wins a little with high probability, and loses 63 USDT about 1.8% of the time. Multiplying the survival chance across all 50 cycles (the bankroll covers 7 losses once it passes 127 USDT, still within the 100 USDT table max) gives an exact chance of reaching the target of about 48.8%, ignoring the 1,000-spin cap.
What our 50,000-session simulation shows
That exact figure is within a few tenths of a point of our stored simulation, which played martingale on red at a single-zero wheel with the default settings above. Here it is next to flat betting:
| System | Reached +50 USDT | Busted or stuck | Average result | Average wagered | Loss per 100 wagered |
|---|---|---|---|---|---|
| Martingale | 48.67% | 51.33% | -6.46 USDT | 233.3 USDT | 2.77 USDT |
| Flat 1 USDT | 2.43% | 1.69% | -26.81 USDT | 989.4 USDT | 2.71 USDT |
Martingale reached the target far more often than flat betting, and lost less per session on average, but only because it wagered much less before stopping. Per 100 USDT wagered, both lost close to the 2.70% house edge. The full comparison with D'Alembert and Fibonacci is in our roulette strategy test.
When you press "Run simulation", the calculator plays your settings with your browser's random number generator. Results move by a few tenths of a percent between runs; more sessions give steadier numbers.
Why martingale can't beat the house edge
Doubling doesn't change the odds of any single bet. Every spin still has the same house edge, so the expected loss is the house edge times the total amount wagered, whatever pattern the stakes follow. Martingale reshapes the results into many small wins and a few large losses. It feels like it works because most sessions finish ahead.
The belief behind it, that a win becomes more likely after a run of losses, is the gambler's fallacy. Spins are independent. If you want to limit damage rather than chase a pattern, fixed stop rules do more for you; our stop-loss roulette guide tests several. For blackjack, see martingale in blackjack, and the odds and strategy math hub has more on expected value.
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Frequently asked questions
How does the martingale strategy work?
You bet a base amount on an even-money bet and double the stake after every loss. When you finally win, you recover all the losses in the sequence plus one base bet, then go back to the base stake. The catch is that bets grow fast: after 10 losses in a row your next 1 USDT-base bet is 1,024 USDT.
How many losses in a row can my bankroll survive with martingale?
Find the largest n where base × (2^n − 1) is no more than your bankroll and the biggest bet, base × 2^(n−1), is within the table max. With 100 USDT and a 1 USDT base, that's 6 losses (63 USDT). With 1,000 USDT it's 9 losses (511 USDT). Doubling the bankroll adds only one more loss.
Does martingale work in the long run?
No. It changes the pattern of results, not the average. Most sessions end with a small win, and a minority end with a large loss that wipes out many small wins. In our 50,000-session roulette test, martingale lost 2.77 USDT per 100 USDT wagered, in line with the 2.70% single-zero house edge.
Why does the table maximum matter for martingale?
A table limit caps how far you can double. With a 1 USDT base and a 100 USDT table max, the biggest bet you can place is 64 USDT, so you can't fund more than 7 losses in a row however large your bankroll is. Limits are one reason doubling systems fail in practice.
Is martingale better on roulette or dice?
It depends only on the win chance and the house edge. A crypto dice bet with a 49.5% win chance at 2x and a 1% edge loses less per 100 wagered than red on a single-zero wheel (48.65%, 2.70% edge). The streak risk is similar. Enter either set of numbers in the calculator.
Sources
- Martingale Betting System — Wizard of Odds. Martingale does not dent the house edge
- Roulette: House odds — Encyclopaedia Britannica. American wheel about 5.26%; European about 2.7%; en prison about 1.35%; betting systems cannot beat the house edge
- Doctrine of the maturity of the chances — Encyclopaedia Britannica. Gambler's fallacy: falsely assumes plays are dependent
- Roulette Basics — Wizard of Odds. House edge: double-zero 5.26%, five-number bet 7.89%; single-zero 2.70%; triple-zero 7.69%; la partage about 1.35% on even-money bets
- Two Basic Rules of Probability — OpenStax, Rice University. Multiplication rule; independent events