Aurora Finance
Calculator

Position size calculator

Position sizing controls how much of your account is at risk on any single trade. This calculator returns the share count that keeps loss to a defined percentage of the account.

Updated July 2026
$
%
$
$
Shares to buy
100
Dollar risk
$500
Position value
$10,000

How it works

Shares = (Account × Risk%) / (Entry − Stop)
  • Enter account size and the percentage you're willing to risk per trade (typically 0.5–2%).
  • Enter entry price and stop-loss price.
  • The calculator returns share count and total dollar risk.

Worked examples

  • $50,000 account, 1% risk, entry $100, stop $95 → 100 shares, $500 risk.
  • Same trade with stop at $90 → 50 shares, $500 risk (wider stop, smaller size).

Frequently asked questions

How much should I risk per trade?

Most disciplined traders risk 0.5–2% of account per trade. Above 2% and a normal losing streak can seriously damage the account.

Does this replace fundamentals?

No — position sizing controls damage from being wrong. It doesn't tell you what to trade or when.

Related

Risk-reward calculator
Sanity-check trade quality.
Stop-loss (glossary)
Reference definition.
Educational information only. Not personalised financial advice. Consult a qualified professional for decisions specific to your situation.