Standard Deviation (Std Dev) — what it is and how to use it in trading
Definition
Standard deviation (Std Dev) of price is a statistical measure of how spread out the close is around its average over the last period candles. The higher the spread, the less stable the market.
How it works in the builder
The stddev operand takes a period parameter (default 20) and returns a positive number in price units with no upper bound. It is the same statistic Bollinger Bands' width is built from — the bands sit dev standard deviations away from the middle average.
What it looks like on the chart
Drawn as a separate panel as a line bounded below by zero and unbounded above — the line's amplitude visibly grows when volatility picks up and shrinks during calm periods.
Typical use
More often used as a volatility filter before an entry rather than a directional signal — for example, entering only when stddev(20) exceeds a threshold calibrated for the instrument, to filter out an overly quiet, ranging market.
Common pitfalls
The value is expressed in price units, so like ATR it does not compare well across instruments of very different price scale — a fixed threshold needs to be calibrated separately per asset, not carried over between them.
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.