Prop Firm Consistency Rule Calculator
Check whether your best trading day breaches a firm's consistency rule, and what it takes to comply.
A prop firm consistency rule caps how much of your total profit may come from a single day, typically somewhere between 25% and 50%, and this prop firm consistency rule calculator measures your best day against that cap. The rule exists to stop an account passing on one outsized trade, and funded account consistency is assessed at payout as well as at evaluation.
Formula: best day share = best day / total profit x 100
Your figures
Net profit across the period the rule is assessed on.
Profit made on your single most profitable day.
Your firm's cap on any one day's share of total profit. The default is a common shape rather than any firm's rule, and some programmes impose no such cap at all.
Results
Best day's share of profit
30.00%
within the 40% limit
- Largest day the rule allowsAt your current total profit.
- US$4,000.00
- Headroom
- +10.00 pts
What this means
Your best day accounts for 30.00% of total profit, inside the limit with 10.00 percentage points to spare. At the current total, a single day would have to exceed US$4,000.00 to breach it.
- Firms differ on what the rule is assessed against — closed profit, the payout period, or the whole account life. Check your agreement.
- Some firms apply the rule only at payout, others continuously. The difference matters if one day runs unusually well early on.
Best day's share of profit: 30.00%
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Continue with these figures
About the Prop Firm Consistency Rule calculation
It catches people out because it is a ratio rather than a limit on any individual day. A $4,000 day is fine on $10,000 of total profit and a breach on $6,000 of it — the same day, judged differently depending on everything else.
That also means a breach is fixed by trading more, not less. This profit consistency calculator shows where you stand and what additional profit would bring an existing best day back inside the limit.
Prop Firm Consistency Rule formula
best day share = best day profit ÷ total profit × 100
largest day the rule allows, at the current total:
max day = total profit × limit ÷ 100
total profit at which an existing best day complies:
compliant total = best day profit ÷ (limit ÷ 100)- limit
- The firm's cap on any one day's share of total profit.
- total profit
- Net profit across whatever period the firm assesses — check which applies.
Because the rule is a ratio, both numbers matter. Reducing the best day is impossible after the fact, so the only available lever is raising the total — which is why the remedy for a breach is more trading days, not fewer.
Rearranging for the compliant total gives the exact amount needed. A $6,000 best day under a 40% limit requires $15,000 of total profit, so an account at $10,000 needs a further $5,000 earned on other days.
The rule interacts awkwardly with the profit target. An account that reaches its target largely on one day may have passed the target and failed the consistency check simultaneously, which is precisely the outcome the rule is designed to produce.
Prop Firm Consistency Rule: a worked example
A funded account with $10,000 of total profit, of which $6,000 came on the single best day, against a 40% consistency limit.
- Best day share6,000 ÷ 10,000 = 60%
- Limit40%
- Largest day allowed now10,000 × 40% = $4,000
- StatusBreached by 20 percentage points
- Compliant total needed6,000 ÷ 0.40 = $15,000
- Additional profit required$5,000
At 60% the account is outside the rule. Earning a further $5,000 on other days brings the best day down to exactly 40% of a $15,000 total, without giving anything up.
How to use the Prop Firm Consistency Rule calculator
- Enter total profit across the period your firm assesses the rule on — check whether that is the payout period, the evaluation, or the account's whole life.
- Enter the profit from your single best day.
- Enter the firm's consistency limit as a percentage.
- If you are in breach, read the additional profit required. That is what has to be earned on other days.
Limitations of the Prop Firm Consistency Rule calculator
Every calculation makes assumptions. These are the ones that matter here.
- Firms differ on what the rule is assessed against and when. Some check only at payout, others continuously.
- Some firms apply the rule to the largest single trade rather than the largest day, which is a stricter test.
- Assumes total profit is net. If your firm assesses gross profit before losing days are deducted, the share will differ.
- Does not model firms that scale the limit with account size or with the number of trading days.
Frequently asked questions about Prop Firm Consistency Rule
Is the consistency rule the same as the best day rule?
They are two names for one test. Prop firm traders tend to say best day rule, because what is measured is your single best day expressed as a share of total profit, and that share is exactly what the calculator reports alongside the total at which it would comply.
Why do firms have a consistency rule?
To distinguish a repeatable process from a single fortunate trade. An account that makes its entire target on one position has demonstrated an outcome rather than a method, and the rule is designed to filter exactly that.
I have breached it. Can I fix it?
Usually yes, by trading more. Because the rule is a ratio, additional profit on other days lowers the best day's share without requiring anything to be undone. The calculator shows exactly how much is needed.
Does the rule apply to losing days too?
Most firms apply it only to profitable days, but some assess the largest single-day loss as well. Check the specific terms, since a rule on losses behaves very differently from one on profits.
Is the rule checked at evaluation or at payout?
It varies. Some firms check at both stages, some only before releasing a payout. A rule checked at payout can delay money from an account that has otherwise passed everything.
Last reviewed . See our methodology and editorial policy.
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