What each output means and how to use it when evaluating a prop firm challenge.
ROI
Expected ROI
Your return on the challenge fee, based on the median simulation outcome — not the average. Median is used because it's more robust to the extreme outlier runs that skew the average upward. An ROI above 100% means the typical funded trader with your stats earns back more than double the fee.
Break-Even
Break-Even in Payout Cycles
How many payouts it takes to fully recover the challenge fee and activation cost. Displayed as "after 1st payout", "after 2nd payout", etc. This is far more meaningful than a trading-days figure — payouts only happen when you clear the profit threshold, typically every 1–2 weeks.
Per Payout
Expected Per Payout
What you can realistically expect to withdraw each time you hit the payout threshold. Calculated as your monthly average profit scaled to the payout interval. For a biweekly payout firm, this is roughly half your monthly average — the number to compare against your challenge fee.
Median
Median Profit
The middle outcome across all 1,000 simulations — half finish above this number, half below. Unlike average profit, median isn't skewed by a few extreme winning runs. This is the outcome you should realistically plan around. P10 and P90 show your realistic downside and upside range.
Blowout
Blowout Probability
The percentage of simulations where your account hits the maximum drawdown limit and gets terminated. A blowout rate above 40% means the challenge is statistically stacked against you at your current risk level. Trailing drawdown firms (Topstep, Apex) typically have tighter limits than static drawdown firms.
Implied Monthly
Implied Monthly Return
A linear estimate of your monthly return based purely on your EV per trade and trades per day — before any drawdown or payout rules are applied. Compare this to the median simulation result: a large gap between the two means drawdown rules are materially cutting into your theoretical edge.
Prop Firm vs. Trading Your Own Capital
The appeal of prop firm trading is access to large account sizes without risking your own money beyond the challenge fee. But the profit split, drawdown restrictions, and challenge costs change the math significantly. Here's a side-by-side comparison.
| Factor |
Personal $25K Account |
$100K Prop Firm (80/20 Split) |
| Capital at risk |
$25,000 (your money) |
$500 challenge fee |
| Buying power |
$25,000 |
$100,000 |
| Profit on a 10% return |
$2,500 (keep 100%) |
$8,000 (keep 80%) |
| Max drawdown allowed |
No external limit |
5-10% (firm rules) |
| Daily drawdown limit |
None |
2-5% (varies by firm) |
| Upfront cost |
$25,000 |
$155-$500 (challenge fee) |
| If you blow the account |
Lose real capital |
Lose the challenge fee only |
| Best for |
Traders with capital & no time pressure |
Consistent traders with limited capital |
Key takeaway: Prop firms make financial sense when your expected profit after the split exceeds what you'd earn trading your own, smaller account — and when your strategy can survive the drawdown rules. This calculator runs the numbers so you don't have to guess. Once you're live, Prop Firm Sync keeps every funded account's P&L, limits, and payout schedule in one dashboard.
Prop Firm ROI Formulas
The core formulas driving this calculator. Understanding them helps you spot which variable has the biggest impact on your profitability.
Expected Value per Trade
EV = (Win Rate × Avg Win %) − (Loss Rate × Avg Loss %)
With a 52% win rate, 1.2% average winner, and 1.0% average loser: EV = (0.52 × 1.2%) − (0.48 × 1.0%) = 0.624% − 0.48% = +0.144% per trade. Positive EV is the minimum requirement for any prop firm attempt — a negative EV strategy loses money no matter how good the risk management.
Implied Monthly Return
Implied Monthly = EV × Trades per Day × 21
At 0.144% EV with 3 trades per day over 21 trading days: 0.144% × 3 × 21 = ~9.1% implied monthly. This is the theoretical ceiling before drawdown rules, payout thresholds, and unlucky trade sequences reduce it. The Monte Carlo median will typically be lower.
Expected Per Payout
Per Payout = Monthly Avg Profit × Payout Interval Days ÷ 21
If your simulation produces a monthly average of $4,800 and your firm pays out biweekly (every 10 trading days): $4,800 × 10 ÷ 21 = ~$2,286 per payout. Compare this directly against your total fee cost to gauge how quickly you'll recover the investment.
Break-Even in Payout Cycles
Break-Even = ⌈ Total Fee Cost ÷ Per-Payout Profit ⌉
If your total cost (challenge fee + activation fee) is $549 and you earn $2,286 per payout, break-even = ⌈549 ÷ 2286⌉ = 1 payout cycle. The calculator displays this as "after 1st payout", "after 2nd payout", and so on — a more realistic framing than days, since payouts require hitting the profit threshold first.
ROI on Challenge Fee
ROI = Median Net Profit ÷ Total Fee Cost × 100
The calculator uses median profit from the 1,000 simulations — not the average — because the average is pulled upward by outlier runs. Median ROI tells you what the typical trader with your stats will actually experience after the split and any applicable fee refund.
Why Monte Carlo matters here: A single EV calculation tells you what should happen on average. But prop firms don't care about your average — they care about your worst drawdown during a specific sequence of trades. Monte Carlo simulation tests 1,000 different orderings of your wins and losses, models the payout threshold, and detects blowouts mid-path to show what actually happens in practice. Note that trailing drawdown firms (Topstep, Apex) use a dollar-based floor capped at your starting balance — a meaningfully tighter constraint than percentage-of-peak drawdown firms.
Worked Example: Is an FTMO $100K Challenge Worth It?
Let's walk through a real scenario. Suppose you have these stats from 6 months of journaling in your TradeZella journal:
| Metric |
Your Value |
| Win rate | 52% |
| Average winner | 1.2% of account |
| Average loser | 1.0% of account |
| Trades per day | 3 |
| FTMO $100K challenge fee | $549 (refundable on first payout) |
| Profit split | 80% to you |
| Max drawdown | 10% static |
| Payout frequency | Biweekly (every 10 trading days) |
Step 1 — EV per trade: (0.52 × 1.2%) − (0.48 × 1.0%) = 0.624% − 0.480% = +0.144%
Step 2 — Implied monthly (before rules): 0.144% × 3 trades/day × 21 days = ~9.1% gross, or ~$9,072 on a $100K account before the split
Step 3 — After FTMO's 80/20 split: $9,072 × 0.80 = ~$7,258/mo in theory
Step 4 — Monte Carlo median (what actually happens): After modeling 1,000 paths with the 10% static drawdown and biweekly payout threshold, the simulation returns a median monthly profit closer to ~$5,200 — drawdown rules and unlucky streaks cut the theoretical ceiling by roughly 28%.
Step 5 — Per payout: $5,200 × 10 ÷ 21 = ~$2,476 per biweekly payout
Step 6 — Break-even: ⌈$549 ÷ $2,476⌉ = after the 1st payout. Because FTMO refunds the challenge fee on your first successful payout, the net cost to get started is effectively zero once you pass.
Step 7 — ROI: Median net profit over 6 months ÷ $549 challenge fee = well above 1,000% — the leverage of a $549 fee controlling $100K of buying power makes the ROI figure very large for any consistent edge.
The lesson: The implied monthly figure tells you the destination. The Monte Carlo median shows you what actually lands in your pocket after drawdown rules, payout thresholds, and trade sequence variance. A gap of 20–30% between the two is normal. A gap above 50% is a signal that the firm's drawdown rules are too tight for your current risk level — and you should reduce position size before paying the fee.
Know Your Numbers Before You Pay the Fee
TradeZella tracks your win rate, average win/loss, drawdown, and trade frequency automatically from your broker sync. Already funded? Prop Firm Sync tracks your account rules, P&L, and payout schedule — all in one place.
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