Position size calculator

The idea in one paragraph

Most sizing mistakes come from starting at the wrong end: “how many shares can I afford” instead of “how much am I willing to lose if my stop hits”. Fix the loss first, in dollars. If your account is $1,000 and you risk 1%, a losing trade costs $10, which stings but changes nothing. The stop distance then dictates the share count mechanically: a $5 gap between entry and stop means $10 of risk buys exactly 2 shares. Wider stop, smaller position; tighter stop, bigger position. The risk stays constant, which is the entire point.

Fractional shares make this clean on Binance: the calculator’s output does not need rounding to whole shares when $5 slices are available. If the suggested position value comes out above your account size, this page caps it and tells you, because the stock desk is cash equities: there is no margin to lean on, which for beginners is a feature.

What this page will not do

• Pick your stop for you. A stop belongs at the price where your trade idea is wrong, not at a round number this tool invents.
• Model fees or slippage. On liquid names these are small; the break-even calculator handles them explicitly.
• Judge the trade. A perfectly sized bad idea is still a bad idea; sizing just makes it survivable. The risk guide is the sober companion read.