ClearPath Trader

Bollinger Bands

A middle SMA with upper/lower bands at a multiple of standard deviation. Band squeezes precede volatility expansions; touches can mark extremes in ranging markets.

Category: Volatility · Complexity: ★★★☆☆ (3/5)

Tags: volatility, live-overlay, volatility

Live chart overlay: BB

Bollinger Bands chart illustration

Formula

Middle = SMA(n); Upper/Lower = Middle ± k·σ(n)

How to read

Squeeze (narrow width) often precedes expansion. Band walks happen in trends; fades work better in ranges.

Limitations

σ assumes a stable distribution. Breakouts can fail; touches are not automatic reversals.

Typical settings

20, 2σ

Bollinger Bands is part of the ClearPath Encyclopedia of Indicators — 190 models explained with standard SVG illustrations, so you can study an indicator before you put it on a live chart.

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