Position size calculator
Enter what you are willing to lose and where your stop belongs. The calculator returns the position size that keeps those two facts consistent. This is the arithmetic from Lesson 1, done for you.
How it is calculated
Risk budget = equity × risk %. Loss per unit = stop distance × value per point, plus the round-trip cost if you entered one. Position size = risk budget ÷ loss per unit.
Two consequences worth internalising: a wider stop does not increase your risk if the size shrinks with it, and costs eat into the same budget as the stop — on short-term trades that is not a rounding error.
What it does not do
It does not know your instrument's contract size, your broker's swap, or how price gaps behave over a weekend. A stop is an instruction, not a guarantee: in fast markets the fill can be worse than the level, so treat the result as the smallest sane maximum, not a target to reach for.