Smart risk management is what separates traders who last from those who blow up. This calculator answers the single most important question before any trade: how many shares should I buy so that, if my stop is hit, I only lose what I planned to?

$
$
$
$
Position size
—
Position value
—
Amount at risk
—
Risk / share
—
Risk : reward
—

Educational tool only — not financial advice. Position size = (account × risk%) ÷ (entry − stop). Always account for commissions, slippage, and gaps; markets can move past your stop.

How it works

The calculator uses the standard fixed-fractional position-sizing formula:

Shares = (Account size × Risk %) ÷ (Entry price − Stop-loss price)

  • Amount at risk is the dollar amount you’d lose if the stop is hit — kept to a small, fixed fraction of your account (many traders use 1–2%).
  • Risk per share is the distance from your entry to your stop.
  • Risk : reward compares your potential loss to your potential gain when you add a target price. A ratio of 1:2 or better is a common benchmark.

Tips for using it well

  • Keep risk per trade small and consistent — consistency beats big swings.
  • Set your stop based on the chart (structure, volatility), then let the math decide the size — not the other way around.
  • Remember real-world frictions: commissions, slippage, and overnight gaps can push losses beyond your planned stop.

This tool is for education only and is not financial advice. Trading involves substantial risk of loss.