Position Size Calculator

How to use a position size calculator the way pros do

The single most expensive mistake retail traders make is sizing trades the same dollar amount every time, instead of the same risk amount. A 10-pip stop and a 100-pip stop are not the same trade — and they shouldn't be the same size.

The fix is brutally simple. Decide what % of your account you're willing to lose if the stop hits — typically 0.5%–2%. Then back-calculate the position size from your entry and stop. This calculator does the math instantly. Use it before every single trade.

Worked example

$10,000 account, 1% risk = $100 at risk. Entry $100, Stop $98 — that's $2 per unit. $100 ÷ $2 = 50 units. If your stop hits, you lose exactly $100. If your account grows to $12,000, 1% becomes $120 — your size automatically scales with the account.