Position Size Calculator
Work out the correct forex position size for your risk. Enter account balance, risk %, and stop-loss in pips to get your lot size instantly.
Size your trade to your risk, not your hope
Position sizing is the single most important risk-management decision a trader makes. Instead of guessing a lot size, you decide how much of your account you are willing to lose on the trade, then let the maths give you the size that respects it.
How to use this calculator
Enter your account balance, the percentage you are willing to risk on this trade (many traders cap this at 1β2%), your stop-loss distance in pips, and the pair. The calculator returns the amount at risk and the corresponding position size in units and lots.
The formula
Position size = (Account balance Γ Risk %) Γ· (Stop-loss in pips Γ pip value per unit)
A tighter stop lets you trade a larger size for the same risk; a wider stop requires a smaller size. The risk in currency terms stays constant β that is the point.
A note on account currency
This calculator assumes your account currency matches the pair’s quote currency. If it differs, apply the quote-to-account exchange rate. Never risk money you cannot afford to lose, and remember that leverage magnifies losses as well as gains.
For information and education only β not financial advice. Verify figures with your broker before trading. See our editorial policy.