Pass-odds calculator
How likely are you to hit the profit target before the drawdown, given your rules and your trading? Enter the numbers, or start from a firm preset.
Results
What does a pass cost at these odds? Open the cost-per-pass calculator
How the calculator works
Each simulated challenge starts at 0% and places trades that risk a fixed percentage of the starting balance. A trade wins with your win rate and pays reward:risk times the risk, otherwise it loses the risk. Every trade also pays your costs, given in R (for example a 0.5-point spread on a 10-point stop is 0.05R). The challenge passes when equity reaches the target, and fails when it touches the max drawdown or the daily loss limit.
- Static drawdown: the floor stays at starting balance minus the max drawdown.
- Trailing drawdown: the floor follows the highest balance, either at each day’s close or after every closed trade. Some firms stop trailing once the floor reaches the starting balance; tick the box for that.
- Daily loss limit: measured from the balance at the start of each day, in % of the starting balance. Some firms fail you (most CFD firms); others just pause you for the day (for example Topstep’s optional DLL and Apex’s EOD DLL).
When the drawdown is static and the daily limit and time limit cannot bind, there is a formula. With 1:1 trades and no costs it is the classic gambler’s ruin: starting d steps above ruin with a target u steps up and win probability p,
P(pass) = (1 − (q/p)^d) / (1 − (q/p)^(u+d)), q = 1 − p
and for p = q = ½: P(pass) = d / (u + d)
Otherwise the calculator shows a drift-diffusion approximation, P = (1 − e^(−2μD/σ²)) / (1 − e^(−2μ(T+D)/σ²)), where μ and σ² are the mean and variance of one trade. That is why the zero-edge benchmark is D/(T+D): see the real odds of passing with no edge.
What it leaves out
- Trades are independent. Real results come in streaks, and open trades can dip below the stop (gaps, slippage), which makes breaches more likely.
- Risk is a fixed % of the starting balance; it doesn’t shrink after losses.
- Consistency rules, minimum trading days and news rules aren’t modelled. Firms differ on whether the daily limit uses balance or equity. Check your firm’s exact wording.
- Your real win rate and reward:risk are estimates. If they came from a backtest you optimised, assume they are too optimistic.