Position Size Calculator

Use this position size calculator to size a trade from risk per trade, entry, stop loss, fees, and an optional execution cushion, then review trade size.

Last updated 30 April 2026

Size the trade from the loss you are willing to take at the stop Position sizing starts with risk budget, not conviction. This calculator works backward from account size, risk tolerance, entry, and stop so the planned loss stays inside the chosen budget before the order is placed.

Direction

Asset type

Account size ($) Risk per trade (%)

Common risk-per-trade presets

Entry price ($) Stop price ($)

Target price (optional $) Round-trip fees ($) Execution cushion per unit (optional $)

Add a small execution cushion if you want the calculator to reserve extra risk for slippage, spread widening, or imperfect stop fills instead of assuming a perfectly clean exit.

Display currency

Switch displayed monetary values without changing the position-size arithmetic.

Currency

Result

62

Shares to trade at $48.00 with a stop at $44.00 while keeping the planned loss near $250.00.

Risk budget is the limiting factor The stop distance and round-trip fees are the main constraint, so the recommended size keeps total stop loss near the chosen risk budget.

Position value: $2,976.00
Risk at stop: $248.00
Stop distance: $4.00 (8.33%)
Effective risk per unit: $4.00 (8.33%)
Account exposure: 11.9%

Risk budget used

99.2%

Unused risk budget: $2.00 after fees.

Target scenario

$744.00

Net profit at $60.00 with an estimated reward-to-risk ratio of 3.

Loss-streak stress check

If you keep risking 1% of the remaining account on each trade, this shows how quickly repeated stop-outs can create drawdown.

3 losses

$24,257.48

2.97% drawdown; 3.06% needed to recover.

5 losses

$23,774.75

4.9% drawdown; 5.15% needed to recover.

10 losses

$22,609.55

9.56% drawdown; 10.57% needed to recover.

Target scenario break-even rate At the estimated 3 reward-to-risk ratio, this setup would need roughly 25% winning trades before costs and execution differences to break even.

How to use the result

The recommended size assumes the stop will be honored and the trade can be exited near the stop price. Real slippage, overnight gaps, spreads, borrowing costs, and liquidity can produce a larger loss than this estimate.

If you trade products where fills often slip, use the execution cushion to treat the stop as wider than the chart alone suggests. That reduces position size before the order is live instead of hoping the exit will be perfect.

About this calculator

General-reference calculator Reviewed 30 April 2026 Updated 30 April 2026

Editorial responsibility

Calcipedia editorial team

This page is maintained against the site trust model for its topic and updated when formulas, sources, or guidance materially change.

Formula provenance

Formula notes are kept in the page explanation when a named standard or reference materially affects the result.

Methodology

Calculates the risk budget from account size and risk percentage, derives per-unit loss from the entry-to-stop distance, optionally adds an execution cushion per unit for slippage or spread risk, reduces the budget by entered round-trip fees, and then caps the position by whichever is smaller: the risk-based size or the amount the account can fund at the chosen entry price. It also compounds the selected risk percentage across 3, 5, and 10 hypothetical losing trades to show drawdown and recovery-gain context.

Limitations

The execution cushion improves conservatism, but it still cannot fully model real slippage, gaps, partial fills, or platform-specific order behavior.
Treats fees as one fixed round-trip amount rather than variable commissions, spread changes, financing, or borrow costs.
The loss-streak stress check is a simple fixed-percentage scenario, not a forecast, Monte Carlo simulation, or complete trading-system risk model.
The optional reward-to-risk estimate assumes the entered target is reached and the same fee structure applies on exit.
This is a trade-planning tool only and not investment advice, a forex lot calculator, or a suitability determination.

Disclaimer

Use this result as a position-sizing baseline only. If the market is illiquid or prone to gaps, size below the calculated maximum and apply your own execution risk controls.

Formula notes

FINRA — Know your risk tolerance — High-trust investor guidance supporting risk-based decision making.
FINRA — Fees and commissions — High-trust investor guidance explaining why trading and investment costs matter to outcomes.
FINRA — Stop orders: factors to consider during volatile markets — High-trust investor guidance on stop-order behavior and execution risk during volatility.

Change notes

Change note: this page's updated date changes only when the formula, labels, examples, or user guidance materially changes. Cosmetic or deploy-only edits do not refresh the date.

See our calculation methodology and editorial standards, plus the editorial contact route, for how this estimate is produced and corrected.

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Trade Risk

Position size calculator guide: shares or units from account risk, stop distance, and fees

A position size calculator starts with the amount you are willing to lose if the stop is hit and works backward to the number of shares or units that fits that loss budget.

Why position size starts with risk budget

Many traders think first about the chart pattern, conviction level, or upside target. Position sizing flips that order. The first question becomes how much of the account can be put at risk on one idea without undermining the larger plan if the trade fails.

That is why the calculator begins with account size and a risk percentage. A stop price then translates that risk budget into a per-unit loss. Once that number is known, the trade size can be scaled so the planned stop loss fits inside the chosen limit.

Core maths behind the recommended size

Per-unit risk is the distance between entry and stop. For a long trade, the stop must sit below the entry. For a short trade, the stop must sit above the entry. The risk budget is the account size multiplied by the chosen risk percentage, then reduced by any round-trip fees you want included.

The calculator also checks whether the account can actually fund the risk-based size. If the capital needed at the entry price is larger than the account balance, the recommendation is capped by available cash rather than by the stop-distance risk budget.

Risk budget = Account size x Risk percentage

Sets the maximum loss the trader is willing to tolerate on the setup before fees.

Risk-based units = (Risk budget - Fees) / Per-unit stop distance

Converts the risk budget into a maximum number of shares or units using the stop distance.

Position value = Units to trade x Entry price

Checks how much capital the recommended size would actually commit at the entry.

How target price and reward-to-risk fit in

A target price does not decide the position size in this calculator. The size is determined by the stop-distance loss budget. The target is used afterward to estimate potential net profit and the approximate reward-to-risk ratio if the position reaches that target and the round-trip fees remain unchanged.

That order matters because an attractive upside target cannot repair a position that is already too large for the stop distance. Good reward-to-risk does not excuse poor size discipline.

Stress-testing the risk per trade after repeated losses

A single position-size result is useful, but traders also need to understand what happens if several trades fail in a row. The loss-streak stress check applies the chosen risk percentage repeatedly to the remaining account balance, so the output shows drawdown and the gain needed to recover after 3, 5, and 10 stopped-out trades.

This is not a prediction that those streaks will happen. It is a discipline check. If the stress table feels too severe at the chosen risk percentage, the practical answer is usually to lower the risk per trade before looking for a larger target or a tighter stop.

Why the page now uses an execution cushion instead of pretending fills are perfect

Many position sizing mistakes come from treating the chart stop as the whole risk story. Real fills can be worse because of slippage, spread widening, partial fills, or a fast market moving through the stop. That is why this calculator now lets you add an execution cushion per share or unit before the size is recommended.

The logic is simple: if the chart stop is 4.00 away from entry but you want to reserve another 0.25 for imperfect execution, the effective risk per unit is 4.25. That small adjustment reduces the trade size before the order is placed, which is usually safer than discovering after the fact that the real loss was larger than the model assumed.

Effective risk per unit = Stop distance + Execution cushion

Adds a user-entered buffer for slippage, spread, or imperfect fills before position size is calculated.

Which position-size keywords fit this page and which ones do not

This page is a strong fit for searches like position size calculator, trading position size calculator, stock position size calculator, trade size calculator, position size calculator with stop loss, and risk per trade calculator because it works directly from account size, entry, stop, fees, and optional reward-to-risk.

It is not trying to be a full forex lot size calculator, pip-value calculator, MT4 lot size calculator, or futures contract-multiplier tool. Those tools need broker-lot conventions, pip-value conversion, or contract specifications that this calculator does not model. The safest way to use this page is for direct-price instruments where your risk per share or unit is clear from the entry and stop.

What this estimate does not cover

Real execution can be worse than the stop price because of slippage, overnight gaps, bid-ask spread widening, or illiquidity. Those risks are especially important in fast-moving or thinly traded markets and can make the real loss larger than the planned loss.

Use the output as a sizing baseline, not as a guarantee. If the market or instrument can gap violently, many traders deliberately size below the theoretical maximum shown by a stop-distance model.

Further reading

FINRA — Know your risk tolerance — High-trust investor guidance supporting the idea that position size should fit the investor’s risk capacity.
FINRA — Stop orders: factors to consider during volatile markets — High-trust investor guidance explaining why real stop execution can differ from the stop price during volatility.

Frequently asked questions

Why is stop distance more important than confidence in the trade?

Because the stop distance determines how much money is lost per share or unit if the setup fails. Confidence is subjective; per-unit risk is arithmetic. Position size should be anchored to the arithmetic.

Why does the calculator sometimes say the account is cash-limited?

Because the risk-based size may require more capital at the entry price than the account actually has available. In that case, the maximum cash-funded size is smaller than the maximum risk-based size.

Does this guarantee my maximum loss?

No. It assumes the stop can be executed near the stop price. Real losses can be larger if the market gaps, liquidity is poor, or the stop is not honored exactly.

Should I include fees in position sizing?

Usually yes, especially for smaller accounts, frequent trading, or products with wider spreads and higher costs. Fees consume part of the risk budget even before market movement is considered.

Why would I use an execution cushion in a position size calculator?

An execution cushion makes the calculator more conservative by adding extra risk per share or unit for slippage, spread widening, or imperfect fills. That is useful when the chart stop alone is likely to understate real trading friction.

Can I use the same position size for every trade?

Usually not. The position should change when the stop distance, account size, or risk budget changes. A fixed share count ignores the fact that different setups create different per-unit risk.

Why does the calculator show a loss-streak stress check?

Because risk per trade is easier to judge when you can see the compounding effect of repeated losses. The stress check shows balance, drawdown, and recovery gain after several stopped-out trades at the selected risk percentage.

Is this the same as a forex lot size calculator?

Not exactly. This page works best when your risk per share or unit is visible directly from the entry and stop price. If you need pip-value conversion, broker lot rules, or contract-specific sizing, a dedicated forex lot size calculator or futures sizing tool is a better fit.

Can I use this for crypto position sizing?

Yes, if you are sizing a trade from direct entry and stop prices and you understand the instrument's actual fill and leverage rules. If leverage, liquidation, maintenance margin, or contract multipliers matter, treat this as a baseline risk worksheet rather than a complete exchange-specific calculator.

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