A prop-firm evaluation is a math problem wearing a trading costume: reach the profit target without touching the daily loss limit or the maximum drawdown. Most failed evals are not strategy failures — they are sizing failures, where one ordinary losing streak intersects a limit the trader never converted into trade counts.
Enter your firm’s rules and your risk per trade. The calculator translates the percentages into cash, into “how many full losers until I breach”, and into how many trades the target realistically takes at honest expectancies.
The two numbers that fail evals
“Full losers to daily limit” is the one to respect: at 2% risk against a 5% daily limit, two consecutive stop-outs put the third trade in breach territory — a completely ordinary morning for a 40%-win-rate system. The standard discipline is sizing so the daily limit absorbs at least three full losers, which is what the suggested-risk figure computes.
“Trades to target” calibrates patience. At 1% risk and a realistic +0.2R expectancy, an 8% target needs about 40 trades — several weeks of disciplined trading, not a heroic week. Evals are usually lost by traders trying to compress that math, not by traders lacking an edge.
Rehearse the eval before paying for one
The rules above can be practiced on historical data before a firm charges you for the attempt: Secuora’s replay backtester has a prop-firm challenge mode where you set the account size, profit target, and daily/total loss limits, then trade real past markets against those rules bar by bar. Failing a rehearsal costs nothing and teaches the same lesson.
Frequently asked questions
How much should I risk per trade in a prop firm challenge?
Size so your daily loss limit absorbs at least three full losers — for a 5% daily limit that means at most about 1.6% risk per trade, and many funded traders go materially lower. The max-drawdown limit then sets the longer leash: at 1% risk against a 10% static drawdown, you can survive roughly ten full losers overall.
How many trades does it take to pass an evaluation?
Target ÷ (risk per trade × expectancy in R). An 8% target at 1% risk needs about 80 trades at +0.1R expectancy, 40 at +0.2R, or 27 at +0.3R. If your honest expectancy is unknown, that is the thing to measure first — in a backtest, not in the eval.
What is the difference between static and trailing drawdown?
Static drawdown measures from your starting balance; trailing drawdown follows your equity high-water mark up, so profits raise the floor beneath you. This calculator assumes static — trailing rules (Topstep and Apex style) are stricter, so treat its drawdown answers as upper bounds there.