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INTERACTIVE TOOL

Position Size Calculator

Good risk management starts before the trade: decide how much of your account you are willing to lose, and let that set the position size. This calculator takes your account value, the share of it you will risk, your entry, and your stop distance, then returns how many shares to buy so a stop-out costs exactly your budget. It also caps the position at a maximum share of your portfolio, so a single idea can never sink the account.

Position size
62 sh
Stop-loss (auto)
$92.00
Position value
$6,200.00
% of portfolio
12.4%
Dollar risk
$496.00
Risk % of account
0.99%

Sized to risk $496.00 (0.99% of your account). Buy 62 shares with your stop 8% below entry, at $92.00.

Formula used

shares = (account × risk%) ÷ (entry × stop%)  ·  capped at (account × maxPos%) ÷ entry

Your risk budget (account × risk%) divided by the per-share loss at your stop gives the share count, so a stop-out costs exactly your budget. The position is then capped at your chosen share of the portfolio. Stop price = entry × (1 − stop%). Shares are rounded down.

Free and private: the numbers you enter stay in your browser. Educational only, not investment advice.

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