Prop-challenge maths: drawdown and consistency rules
Verify whether your daily risk budget, best single-day profit and cumulative profit stay inside evaluation drawdown and consistency rules.
How Evaluation Drawdown and Consistency Rules Work
Many proprietary trading evaluations set three numerical limits (each firm publishes its own, and they change, so check the current rules): a Daily Loss Limit (often 4% to 5% of initial balance), a Maximum Overall Drawdown (often 8% to 10%), and a Consistency Rule stating that no single trading day may account for more than 30% to 40% of your total cumulative profit. Because a 10% maximum drawdown is your true risk capital—not the nominal $100,000 headline balance—risking 1% of the nominal balance ($1,000) actually risks 10% of your allowable drawdown on a single trade.
Independence notice: TradeProfy is an independent educational calculator and is not affiliated with, endorsed by, or partnered with any proprietary trading firm, nor does it promise payouts or funding.
Worked example
A $100,000 evaluation has a 10% profit target, a 5% daily loss limit and a 10% total loss limit. That is a $10,000 target, a $5,000 daily limit and a $10,000 total limit. Risking 0.5% ($500) per trade, ten full losses in a row would reach the daily limit and twenty would reach the total limit, before costs. Risking 1% halves both numbers.
For the consistency rule, suppose your best day made $2,400 and your total profit is $8,200. The best day is 2,400 ÷ 8,200 = 29.3% of the total, just inside a 30% rule. If you stopped at $7,000 of profit, the same best day would be 34.3% and outside the rule, so you would need at least $8,000 of total profit for that day to fit.
Static and trailing limits
Some firms measure the total loss limit from the starting balance (a static limit). Others let it follow your highest balance (a trailing limit), so gains raise the floor and give you less room later. Check which one your firm uses and whether the daily limit is measured from the start-of-day balance or equity, because each version changes how much you can risk on a single day.
Plan individual trades against these limits in the Trade Planner by entering the daily loss budget under “Costs, leverage & limits”, and test how often a run of losses would breach them in the Risk Lab.
Frequently asked questions
Why is risking 1% of a nominal $100,000 evaluation account risky?
If your maximum allowed loss is 10% ($10,000), a $1,000 loss consumes 10% of your actual survival buffer. For this reason many evaluation traders size well below 1% of the nominal balance; the right figure depends on the firm’s rules and your own plan.
How is the consistency rule percentage calculated?
Divide your highest single-day dollar profit by your total cumulative profit. If your best day is $2,400 and total profit is $6,000, your best day represents 40% of total profit.
Written and maintained by Mantu Kumar
Mantu builds TradeProfy’s calculation engines and checks every formula with worked examples and lists the sources and assumptions on each page. TradeProfy is an educational maths and risk-planning platform and never tells you what to buy or sell.
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