Position sizing

Fixed-fractional sizing risks the same share of your account on every trade, typically 0.5% to 2%. The stop sets the risk per share, and the size follows from it:

With $25,000 and 1% risk the budget is $250. A stop $1.50 away allows 166 shares; a stop $5 away allows 50. The dollar risk is the same; the position value is very different. That is the point: the stop decides the size, not the other way round.

Round down, never up, so you never risk more than planned. When the stop is very tight the size can exceed your buying power; then leverage caps it and you risk less than your budget.