Position Size Calculator
Calculate position size (shares) for long or short trades based on your account size, risk tolerance, and stop loss level. Essential for proper risk management.
Enter your account size, risk percentage, entry price, and stop loss, then click Calculate position size to see the recommended number of shares.
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Not sure which sizing method to use? Compare Position Size vs Kelly Criterion →
Want the full context? See the full trade planning workflow →
Position Size Formula
Dollar Risk = Account Size × Risk %
Risk Per Share = |Entry Price - Stop Loss|
Position Size = floor(Dollar Risk ÷ Risk Per Share)
Works for both long and short positions. Shares are floored to whole units.