Stop-Loss Calculator: method, checked example and practical limits
Derive a stop price or maximum loss from entry, position size and risk assumptions. The resulting stop level expresses a planned exit assumption rather than a guaranteed execution price.
Inputs used by this calculator
Stop-Loss Calculator uses the fields below. The starting values reproduce the page example; replace them with values from the same units and time period before using the result.
| Input | Starting example | Accepted value | How it is used |
|---|---|---|---|
| Position direction | Long | Long · Short | Supplies the position direction quantity used by the published equation or result breakdown. |
| Solve for | Stop price from max loss | Stop price from max loss · Loss from entered stop | Chooses which Stop-Loss Calculator method or unknown the engine evaluates. |
| Entry price | 100 | 0.000001 to 1000000000000000 | Supplies the entry price quantity used by the published equation or result breakdown. |
| Position units | 50 | 0.000001 to 1000000000000000 | Selects the unit or conversion path used by Stop-Loss Calculator. |
| Maximum price loss | 250 | 0 to 1000000000000000 | Supplies the maximum price loss quantity used by the published equation or result breakdown. |
| Entered stop price | 95 | 0 to 1000000000000000 | Selects the unit or conversion path used by Stop-Loss Calculator. |
| Round-trip fees | 10 | 0 to 1000000000000 | Supplies the round-trip fees quantity used by the published equation or result breakdown. |
Inputs and measurement conventions
The quantities used on this page are Position direction, Solve for, Entry price, Position units, Maximum price loss, Entered stop price, Round-trip fees. Start with values for the same situation and read the units attached to each field. The field reference below shows supported choices and numerical limits.
A stop order becomes subject to market execution rules. Tick size, gaps and contract multipliers can change actual risk.
Method and equation
Subtract assumed fees from a maximum-loss budget and divide the remaining allowance by position units to obtain adverse price distance.
Stop-Loss Calculator uses the following stated relationship: stop distance = (maximum loss − fees) ÷ position units. Its assumptions determine which question the answer can resolve.
stop distance = (maximum loss − fees) ÷ position unitsWorked calculation with the starting values
Position direction: Long; Solve for: Stop price from max loss; Entry price: 100; Position units: 50; Maximum price loss: 250; Entered stop price: 95; Round-trip fees: 10. These starting values give 95.2 calculated stop price. The calculation breakdown is Price distance: 4.8; Position notional: 5,000; Fees: 10; Direction: long.
A $250 loss budget, $10 fees and 50 units gives $4.80 price distance.
Reading the answer
The resulting stop level expresses a planned exit assumption rather than a guaranteed execution price.
Price distance: 4.8; Position notional: 5,000; Fees: 10; Direction: long. These intermediate quantities make the stated Stop-Loss Calculator model inspectable; they should be read together with the main answer rather than treated as independent guarantees.
Common errors and model boundaries
A stop order becomes subject to market execution rules. Tick size, gaps and contract multipliers can change actual risk.
A stop order does not guarantee execution at the stop price during gaps, volatility or illiquidity.
Independent verification and next decision
No. Volatility and illiquidity can lead to execution elsewhere or failure to fill, depending on order type.
For the Stop-Loss Calculator method, compare stop distance = (maximum loss − fees) ÷ position units with the starting inputs and the calculation table. The linked Investor.gov: investing basics and FINRA: investing references identify the relevant definitions, conventions or domain limitations. Retain intermediate precision when comparing a manually worked answer.
Stop-Loss Calculator worked-example ledger
| Quantity | Example value | Role |
|---|---|---|
| Position direction | Long | Entered assumption |
| Solve for | Stop price from max loss | Entered assumption |
| Entry price | 100 | Entered assumption |
| Position units | 50 | Entered assumption |
| Maximum price loss | 250 | Entered assumption |
| Entered stop price | 95 | Entered assumption |
| Round-trip fees | 10 | Entered assumption |
| Main answer | 95.2 calculated stop price | Calculated from the starting inputs |
| Price distance | 4.8 | Intermediate or contextual output |
| Position notional | 5,000 | Intermediate or contextual output |
| Fees | 10 | Intermediate or contextual output |
| Direction | long | Intermediate or contextual output |
Frequently asked questions
Can a stop always execute at the displayed price?
No. Volatility and illiquidity can lead to execution elsewhere or failure to fill, depending on order type.
Which relationship does the Stop-Loss Calculator use?
Subtract assumed fees from a maximum-loss budget and divide the remaining allowance by position units to obtain adverse price distance. The displayed relationship is stop distance = (maximum loss − fees) ÷ position units.
What do the starting values produce in the Stop-Loss Calculator?
Position direction: Long; Solve for: Stop price from max loss; Entry price: 100; Position units: 50; Maximum price loss: 250; Entered stop price: 95; Round-trip fees: 10. These starting values give 95.2 calculated stop price. The calculation breakdown is Price distance: 4.8; Position notional: 5,000; Fees: 10; Direction: long.
How should I interpret this Stop-Loss Calculator answer?
The resulting stop level expresses a planned exit assumption rather than a guaranteed execution price.
Which input mistake most affects the Stop-Loss Calculator?
A stop order becomes subject to market execution rules. Tick size, gaps and contract multipliers can change actual risk.
What is outside this Stop-Loss Calculator model?
A stop order does not guarantee execution at the stop price during gaps, volatility or illiquidity.
What to keep in mind
A stop order does not guarantee execution at the stop price during gaps, volatility or illiquidity.
Results are rounded for display in US format, with money in dollars and cents; CSV exports keep full calculation precision. This is a calculation summary, not an official certificate.