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Position Size Calculator

Work out exactly how many units to buy so a stop-loss hit costs you a fixed, pre-decided amount — not whatever the market feels like taking.

Position size
Amount at risk
Risk per unit
Stop distance
Position value
Leverage needed

Currency-agnostic: put your balance in whatever unit your account uses and the results come back in the same one. Nothing you type leaves your browser.

The formula

Position sizing is three lines of arithmetic that most blown accounts skipped:

  1. Amount at risk = account balance × risk %
  2. Risk per unit = | entry price − stop price |
  3. Position size = amount at risk ÷ risk per unit

Worked example, using the defaults above: a 10,000 account risking 1% is risking 100. Entry at 68,400 with a stop at 67,200 means each unit can lose 1,200. So 100 ÷ 1,200 = 0.0833 units. If the stop is hit, you lose 100 — regardless of how big the position looks.

Why the stop comes first, not the size

The common failure is backwards: pick a position size that feels right, then place the stop wherever it fits. That makes your loss a function of your mood.

The correct order is the opposite. The stop belongs where the idea is proven wrong — a structural level, not a round number and not a comfortable distance. Then the size is derived from it. A wider stop doesn't mean more risk; it means a smaller position. This calculator only works if you decide the stop first.

About the leverage line

If the position value exceeds your balance, the calculator shows the leverage that implies. That's a consequence of your inputs, not a recommendation. A tight stop can produce a mathematically "safe" 1% risk that still needs 8× leverage to express — and leverage brings liquidation risk that sits outside this arithmetic entirely.

What this calculator does not include

FAQ

What percentage should I risk per trade?

Common practice is 0.5%–2% of account equity per trade, with most conservative guidance clustering around 1%. The honest answer is that it depends on your edge, your drawdown tolerance and how correlated your positions are — but if you don't have a number decided in advance, you're sizing by feel.

Does this work for forex, crypto and stocks?

Yes — the arithmetic is unit-agnostic. "Units" means shares, coins, or contracts depending on your market. For forex, convert the result to lots using your broker's contract size.

Should the stop be a percentage or a level?

A level. A stop placed at "2% below entry" is arbitrary; a stop placed below the structure that invalidates your idea is information. Size adapts to the stop, not the other way round.

Is my data stored?

No. The calculation runs entirely in your browser — nothing is sent anywhere and nothing is saved.

These numbers tell you how much to risk. They can't tell you whether the setup is worth risking anything on — that's a different question, and it's the one we built Tickrify for: paste a chart, get entry, stop, targets and risk, or an honest "no trade". Three analyses free, no card.

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