Bollinger Band Spread (Dunk)

Bollinger Band Width measures the distance between the upper and lower Bollinger Bands. It reflects market volatility—wider bands mean higher volatility, narrower bands mean lower volatility.

When the width contracts to low levels, it can signal price consolidation and potential breakouts. When the width expands, it indicates active markets or strong trends.

Traders use it to spot volatility squeezes, confirm breakouts, and compare relative volatility across assets or timeframes.