Std deviation

What does Std deviation measure?

How spread out prices have been — the raw, unscaled volatility number that Bollinger Bands are built from.

How is Std deviation calculated?

Take the last 20 closes, work out how far each is from their average, square those distances, average them, and take the square root.

Written by reading the engine’s real computation, not a textbook — where the two differ, the page describes what actually runs.

How do I use Std deviation in a bot?

In the builder, add an indicator of type stddev (parameters: length, default 20). Its value becomes an operand you can compare in any entry or exit rule. The engine grades the whole rule honestly: real fills, no look-ahead, half the history held back.

Related indicators

• True rangeHow far the stock actually travelled in one candle, counting any overnight gap.
• Ulcer indexA volatility measure that only counts the PAIN — how deep drawdowns went and how long they lasted.
• Upper shadowThe wick sticking up above the candle's body — how far buyers pushed before sellers took it back.
• VarianceThe spread of recent prices before the square root is taken — standard deviation's rawer twin, used where the squared scale is wanted.

Or browse all 158 indicators in the full library.