Position size calculator
The trade starts with how much you're willing to lose — not how much you want to make.
How position sizing works
Pick a fixed slice of your account you're willing to lose on any single idea — most disciplined traders use 1–2%. Your share count then falls out of the math: risk budget ÷ (entry − stop) = shares. The stock's price doesn't decide your size; your stop distance does.
Why the 1% rule keeps you alive
Risking 1% per trade means a brutal streak of ten straight losers costs about 10% of the account — annoying, recoverable. Risking 10% per trade, the same streak wipes out nearly two-thirds. The math of drawdowns is cruel: lose 50% and you need +100% just to get back to even. Sizing is how you survive being wrong, and everyone is wrong regularly.
The gap warning
A stop-loss is an instruction, not a guarantee. Stocks gap through stops on earnings and news, and you get the next price, not your price. That's why the calculator flags positions above ~25% of your account even when the stop math looks tidy.
Bobby does this automatically, for every stock you own or watch
Agent Bobby reads the tape, names the catalyst, and tells you why it matters — in the app, every day.
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