Free tool · position size
How big should this trade be?
Decide how much you're willing to lose first, then let the maths set the size. Not the other way round. Enter your stop and see the position, the margin it needs and whether the exchange would liquidate you before your stop.
The formula
Position size = (account × share you're willing to lose) ÷ distance to your stop. With $4,000 and 1% at risk ($40), and a stop 7.5% away, the position is $40 ÷ 0.075 = $533. If the stop is hit, you lose $40, whatever the leverage.
Where leverage really matters
Leverage doesn't change what you lose at the stop. It changes the margin you put up, and where the exchange liquidates you. If the liquidation price sits between your entry and your stop, the exchange closes you first and keeps the whole margin. The calculator warns you when that happens. For one trade's exact liquidation price, use the liquidation price calculator.
Why size from the loss
A string of losers is normal. If every trade risks a small, fixed share, ten losers in a row hurt but don't end you. If the size comes from a feeling, one bad week can. See what a run of losses costs to win back in the drawdown recovery calculator, and how several trades can fail together in the leverage risk check.
For information only, not financial advice. Liquidation is shown for isolated margin before fees; each exchange uses its own mark price and tiers. A stop can fill worse than its price in a fast market.