Prop Firm Calculator

Four independent tools for anyone running a prop firm evaluation: project what steady compounding does to a balance, check your real risk of ruin, work out the expected value of an evaluation before you pay for it, and run a Monte Carlo simulation of your odds against a specific firm's drawdown rules.

Why growth, risk, EV and survival belong on the same screen

Compound growth calculators are everywhere, and they're seductive for a reason — a modest per-period gain, compounded for a year, produces a chart that climbs into numbers that feel inevitable. What most of those calculators leave out is the other half of the same math: the same aggressive risk-per-trade that makes the growth curve steep is very often the exact setting that makes ruin likely, not unlikely. Prop Firm Calculator puts growth and risk in front of you at once, then goes further — before you pay for an evaluation, the EV Calculator tells you whether the pass rate and payout on offer are actually worth the entry fee, and the Survival Simulator runs your specific numbers against a specific firm's drawdown rules thousands of times to show you the real odds, not a marketing pass rate.

What's inside

• Compound growth projector Starting balance, gain per period, and a period unit of day, week or month, projected up to 520 periods — with final balance, total return and total gain, a growth curve chart that auto-switches to log scale past 20×, and milestone markers for 2×, 5× and 10×
• Risk of Ruin Win rate, risk per trade, average reward-to-risk and a ruin threshold you set, producing a risk-of-ruin percentage, expectancy in R, a realistic longest losing streak, and a plain-English verdict on whether your inputs describe a sustainable risk profile or a coin flip
• Prop Firm EV Calculator Evaluation cost, pass rate, payout chance and payout size in, average cost to funded, expected value per evaluation, return multiple, and accounts needed for a target monthly payout out
• Survival Simulator A Monte Carlo engine running thousands of simulated challenge attempts against your win rate, risk per trade and a specific firm's drawdown rules — reporting pass rate, breach rate, and where in the attempt failure typically occurs
• Share your results One tap to share a growth projection or a simulator result
• Private by design All calculations stay on your device — no account, no data collected

How the Risk of Ruin card differs from the Survival Simulator

Risk of Ruin isn't a trade-by-trade simulation — it's the classical closed-form gambler's-ruin result, applied by approximating fixed-fractional risk (a percentage of a balance that itself grows and shrinks trade to trade) as a fixed number of equal capital units. It's a well-established approximation, not a guess, and it comes with an honest caveat: real risk of ruin, once you account for position sizing that compounds and a sensible stopping rule instead of trading forever, is generally lower than what this card shows. The Survival Simulator is the more precise tool for a specific prop firm challenge — it runs a full Monte Carlo simulation against that firm's actual drawdown mechanics rather than a general approximation.

Screenshots

Frequently asked questions

Is the risk of ruin number an exact simulation?

The Risk of Ruin card uses the classical closed-form gambler's-ruin approximation, treating fixed-fractional risk as a fixed number of equal capital units, rather than a full Monte Carlo simulation. The Survival Simulator, by contrast, runs a full Monte Carlo engine against a specific firm's drawdown rules.

What does the Survival Simulator actually simulate?

It runs thousands of simulated challenge attempts using your win rate and risk per trade against a specific prop firm's drawdown rules, then reports your pass rate, breach rate, and where in the attempt failures typically happen.

What does the EV Calculator tell you that a pass rate doesn't?

Given an evaluation's cost, pass rate, payout chance and payout size, it works out your average cost to get funded, the expected value per evaluation, your return multiple, and how many accounts you'd need to hit a target monthly payout.

Does the app store my numbers anywhere?

No. All calculations stay on your device — no account, no cloud, no data collected.

This app is a calculation tool for educational purposes. It does not provide financial, investment or trading advice. Trading involves risk.