Prop firm pass rate calculator: challenge pass probability simulator

How to use it

1. Tap a preset under "Typical rules" if one is close to your challenge: 1-step, 2-step, Instant funding or Futures end of day. These are generic examples, not any firm's rules, so adjust them to match yours. 2. Enter your win rate and your reward to risk. 1.5 means a win makes 1.5 times what a loss costs. 3. Enter your risk per trade, as a share of the starting balance. 4. Enter the profit target, the maximum drawdown and its type (static or trailing), and the daily loss limit (0 if there is none). 5. Enter how many trades you take a day and how many trading days the challenge allows (0 for no time limit, tested up to 250 days). 6. Choose how many challenges to simulate. 10,000 is the default; more runs give a steadier answer, up to 50,000.

The result updates as you change the inputs. The simulation uses a fixed seed, so the same inputs always give the same answer.

How it works

This is a Monte Carlo simulation. Each simulated challenge starts at the starting balance. Every trade is drawn at random: a win at your win rate, a loss otherwise. A win adds your risk times your reward to risk, and a loss takes away your risk. Risk is measured from the starting balance, so it does not grow or shrink with the account.

After every trade the tool checks the rules in order: has equity touched the maximum drawdown floor, has today's loss reached the daily limit, has the account reached the target. A trailing floor follows the highest balance and stops at the starting balance.

The result shows the share of challenges that passed, hit the maximum drawdown, hit the daily limit or ran out of time, plus how many trades a typical pass took (the median) and the breakeven win rate for your reward to risk. A chart draws 30 of the simulated paths, colored by how each one ended, with the target and the limit marked. A trailing limit shows as a band.

Each trade is treated as independent, with the same win rate every time. Real trading does not work like that: losing streaks cluster, markets change, and people trade differently under pressure. Use the result to compare settings, not as a forecast.

Worked example: a futures style account

Take the Futures end of day preset: a 6% target, a 4% trailing drawdown, no daily limit. Add a 45% win rate, a reward to risk of 1.5, 2 trades a day and no time limit. Note that the simulator draws this preset as a trailing limit checked after every trade, which is stricter than a floor that moves only at the close.

1. Breakeven win rate: 1 divided by (1 plus 1.5) is 40%. At 45% the strategy is above breakeven. 2. Average result per trade: 0.45 times 1.5 is 0.675, minus 0.55 times 1, which is 0.55, gives 0.125 times the risk. 3. At 0.5% risk, the target is 6% divided by 0.5%, which is 12 risk units away, and the limit is 8 units below the high. 4. At 2% risk, the target is only 3 units away, so two wins in a row pass, and the limit is 2 units below the high.

With 10,000 runs, the tool gives:

• 0.5% risk: 57.3% pass, 42.7% hit the drawdown, a typical pass takes 40 trades.
• 1% risk: 44.0% pass, a typical pass takes 11 trades.
• 2% risk: 37.7% pass, a typical pass takes 2 trades.

With no time limit, nothing runs out of time. Smaller risk gives the small average edge more trades to work, so more attempts pass, and they take longer.

Common mistakes

• Using a win rate from a few trades. A win rate from 20 trades can be far from your real one. Use the largest record you have.
• Ignoring costs. Commission and spread shrink every win and grow every loss. The risk reward calculator adds costs to the breakeven win rate.
• Reading the result as a forecast. It describes the inputs, not you. Real trades are not independent draws.
• Testing only one risk level. The odds often change more with risk per trade than with anything else. Try 0.5%, 1% and 2%.
• Setting more trades a day than you take. Extra trades in the simulation mean faster passes and faster failures that you would not see.
• Forgetting the daily limit. With 3 losses a day at 2% risk, a 5% daily limit fails the account on a bad day, even with a wide maximum drawdown.

What to check at your firm

• Drawdown type: static, intraday trailing or end of day trailing. Check today's floors with the drawdown calculator.
• Time limits: some challenges have no deadline; others set a number of days per phase.
• Minimum trading days before a pass counts.
• Phases: a two phase evaluation means passing twice, so the combined odds are lower than one run here.
• Consistency rules that can hold back a pass made in a few big days.

Results depend on the inputs you enter, and firms' rules differ, so check your own firm's rules before you trade.

Running a prop firm? Read How much does it cost to start a prop firm? A real budget breakdown.