Ready to go further
Next: work out your own ladder
The martingale calculator gives the number of steps your bankroll allows and the chance of one failed ladder.
What is included
- What it is, in plain words
- The formula or mechanism, with exact arithmetic
- How it hits grid, martingale and DCA bots
- A check you can run before you switch a bot on
Who it is for
- People who run or plan to run a trading bot
- Anyone reading a backtest or a bot sales page
- Readers who want the numbers, not the pitch
- Not advice, and not a signal service
Key facts
- The test: 2,000 made-up bots, each starting with $1,000, betting $10 and doubling after each loss, for up to 500 rounds (calculated by us on 29 Oct 2026).
- A blow-up here means a ladder that cannot pay for its next bet, so everything staked in that round is lost. With this bankroll that takes 6 losses in a row.
- On a fair 50 percent bet, 46.2% of bots had blown up by round 50, 63.5% of bots had blown up by round 100, 84.1% of bots had blown up by round 250, 93.1% of bots had blown up by round 500.
- On a bet with a small edge against you (18 in 37), the same counts were 49.2%, 68.5%, 88.1%, 96.0%.
- The tracker shows when the strategy fails, not whether it is worth running. The small wins are real, and so is the wall.
How the tracker works
Every bot plays rounds. In a round it bets $10. If the bet loses, the next bet is double, and so on until a bet wins or the next bet is more than the money left. A win ends the round with a profit of $10. If the next bet cannot be paid for, the round is a failed ladder: everything staked in that round is lost, and the bot carries on with what is left, at the same $10 start. Because the bankroll is now smaller, its ladder has fewer steps and fails sooner.
Chance a ladder fails = (1 - win chance)^n
Chance of at least one failure in R rounds = 1 - (1 - fail chance)^R
From a full bankroll the ladder is 6 steps deep, so a round fails with a chance of 0.5 to the power 6, which is 1.56% on a fair bet. That sounds small. Over many rounds it is not: the table counts what happened to 2,000 simulated bots.
| Rounds played | Fair bet: blown up by now | Edge against: blown up by now | Fair bet: bankroll below the first bet | Edge against: bankroll below the first bet |
|---|---|---|---|---|
| 50 | 46.2% | 49.2% | 12.7% | 14.6% |
| 100 | 63.5% | 68.5% | 28.4% | 35.7% |
| 250 | 84.1% | 88.1% | 53.1% | 64.3% |
| 500 | 93.1% | 96.0% | 71.0% | 81.7% |
The first blow-up is not the end. After it the bot is poorer and its ladder is shorter, so the next one comes sooner. The last two columns show the share of bots that could no longer place a single $10 bet. After 500 rounds on the fair bet, 22.7% of bots held more than the $1,000 they started with, and 71.0% held less than the first bet. On the bet with an edge against, 14.0% were ahead and 81.7% were below the first bet. The bots that finished ahead are the ones a short test or a screenshot would show.
What the picture and the table say
- The risk grows with time. The share of blown-up bots is not fixed. It climbs each round, so a test that stops early looks safe.
- A small edge against you speeds it up. Compare the two columns. The fair bet is the best case, and real markets add costs. See spread and slippage.
- Recovery is slower than the fall. Each round wins $10, and one failure can cost hundreds. That is the staircase and the cliff in the picture.
- Some bots finish ahead, and they are the ones you see. Early on most are ahead, which is why the strategy looks good in a short test and why a demo account result proves little.
Where bots go wrong with this
- Judging a bot on a short run. Fifty rounds can look clean. See martingale strategy for the exact maths.
- Ignoring that markets are not coin flips. Prices trend, gap and move together, so losing runs come in clumps. The tracker uses independent bets and so understates this.
- Ignoring a stop. A ladder with no cap is limited only by the bankroll or the broker. A cap on steps turns a blow-up into a smaller loss, as in stop loss orders.
- Counting only winners. A published win rate hides the size of the rare loss. Read survivorship bias.
How to check a martingale bot
Ask for the number of steps the bankroll allows, then calculate the chance of one failed ladder with the martingale calculator. Run the rule on long data with full costs and look at the worst drawdown, as in max drawdown. Then check the chance of ruin in the risk of ruin calculator.
What this page does not tell you
It does not say a martingale bot will fail by a given date, or that a different design would not. The bets are independent and made up, the numbers come from a seeded simulation, and this is education, not advice.
Keep Going
Related Tools and Guides
Keep exploring
FAQ
Frequently Asked Questions
What is a martingale blow-up?
It is the point where a doubling ladder cannot pay for its next bet. Everything staked in that round is lost, which can undo many earlier small wins.
How often does a martingale bot blow up?
It depends on the bankroll, the first bet and the win chance. In the simulation on this page the share rose with every round played, as the table shows.
Why does a martingale bot look profitable in a short test?
Because most rounds win a small amount and the failure is rare. A short test can finish before the rare loss arrives.
Does a bigger bankroll fix a martingale bot?
It adds steps to the ladder and makes a failure rarer, but the failure still costs far more than a win pays. The risk is delayed, not removed.
Can a stop limit the damage from a martingale ladder?
A cap on the number of steps limits the loss from one ladder. It also means the ladder can end in a loss that one more step might have recovered.
Are the numbers on this page real?
Example numbers are made up to show how the maths works, and the page says so. A figure only counts as exact when the page says it was calculated on a stated date. Nothing you enter in a calculator leaves your browser.
Can I use this to decide whether to run a bot?
It can show whether a bot's numbers hold together and how much an account can lose. It cannot say what the market will do, and it is not advice. Use it to ask better questions, then read the terms of your own broker or exchange.
Is this financial advice?
No. It is general education about a strategy. The bets and results are made up and it does not consider your situation.
Know the Risk Before You Run It
Free calculators and guides, added every week. Leave your details and we will email you when new ones go up.
Trading carries a risk of loss