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Position Size Calculator

Work out how big a position to take from your account size, risk per trade, and stop-loss distance.

Risk amount
$10.00
Position size
2.0000 units
Notional value
$200.00

Educational tool only — not financial advice. Verify all figures with your platform before trading.

Estimate only — for planning, not financial advice. Your exchange or broker is the source of truth for exact figures.

How it's calculated

Risk amount = balance × risk%. Position size (units) = risk amount ÷ |entry − stop|. Notional = units × entry. This sizes the trade so that hitting your stop loses exactly your chosen risk amount.

Worked example

Say your balance is $5,000 and you risk 1% ($50) per trade. You buy at $100 with a stop at $96, so your stop distance is $4. Position size = $50 ÷ $4 = 12.5 units — a notional of 12.5 × $100 = $1,250. If the stop hits, you lose exactly your planned $50.

FAQ

How much should I risk per trade?
A common rule is 1–2% of your account per trade, so a string of losses can't wipe you out. This calculator turns whatever risk you choose into a concrete position size.
Does position size depend on leverage?
No. Your position size is set by your risk amount and stop distance. Leverage only changes the margin you must post to open that position — not how much you lose if the stop is hit.

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