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Position Size from Stop Loss Calculator

This starts from the opposite question: not "what is my balance?" but "what am I willing to lose on this trade?". Set a risk percentage and a stop distance, and it returns the lot size that puts your loss at the stop exactly inside the limit you drew.

Instrument

Press Calculate to see the result for this balance.

Lot size and reinforcementsWhat size do I open at my balance, and how do I add?Drawdown recoveryWhat gain do I need to get back to where I was?Pip valueWhat is one pip worth in dollars?Compound growthWhere does my balance end up if I withdraw half?If the market goes against youWhere is my account after a 10% adverse move?

How it is worked out

Amount at risk = balance × risk %. Loss per lot = stop distance × the broker's contract size. Lot = amount at risk ÷ loss per lot, **rounded down** to the nearest allowed step. Rounding down is deliberate: rounding up would risk more than the number you typed, which is the one thing this tool must never do.

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The maths assumes your stop fills exactly at its price. In reality slippage and gaps can make the loss larger, especially around news and at the open. Treat the figure as a floor on the loss, not a guaranteed ceiling.

Calculators