Prop Firm Challenge Pass Probability Simulator

It is exact for the assumptions you feed it: the simulator runs 20,000 randomized challenge attempts using your win rate, risk:reward and sizing against the profit target and drawdown rules. Its limits are your inputs — real win rates drift under pressure, so treat results as an upper bound and test with a win rate 5 points below your backtest.

It depends on risk:reward. At 1:2 RR, roughly a 40% win rate gives a strong positive expectancy and a high pass probability at 1% risk. At 1:1 RR you need about 55%+. Below those thresholds, more attempts just resample the same negative expectancy — no firm choice fixes that.

It increases speed and variance at the same time: you pass faster when you pass, but drawdown breaches multiply. For most edges, pass probability peaks around 1–1.5% risk per trade and falls off sharply above 2% — run the simulator at 1%, 2% and 3% and watch the breach rate, not just the pass rate.

Two mathematical reasons: your daily loss limit converts an ordinary loss cluster into a terminal event if you oversize, and 90-day-style expectations push overtrading. A profitable strategy with 1:2 RR and 45% wins still loses 3+ in a row about once every 15 trades — sizing must survive that.