Position Sizing — what it is and how to use it in trading
Definition
Position sizing is the rule for computing a specific trade's size: how much capital to commit on a given entry, independent of the entry and exit rules themselves.
How it works in the builder
The builder offers several modes: full capital, a fixed percent of capital, a fixed cash amount, or risk-based sizing — where position size is derived from the distance to the stop-loss so the trade risks a fixed percent of the deposit (requires a base stop-loss to be set).
Typical use
Risk-based sizing keeps risk constant even when different trades have different stop-loss widths — a wide stop yields a smaller position size, a narrow stop a larger one, but the dollar amount at risk stays the same.
Common pitfalls
Overly aggressive sizing (a large risk percentage per trade) amplifies drawdowns too: a run of several losing trades in a row at 5% risk per trade erodes the account much more than the same run at 1% risk.
This block is available in the strategy builder
137 no-code blocks — build an entry condition with this term and test it on history
Historical results do not guarantee future ones. The service is an informational and analytical tool, not an individual investment recommendation; trades are not executed.