What it does
Bollinger Bands plot a middle line, normally a 20-period simple moving average, with an upper and lower band set 2 standard deviations of price above and below it. Because standard deviation measures how volatile price has been, the bands automatically widen in fast markets and contract in quiet ones. Roughly 90 percent of price action tends to stay inside the bands, so touches of the extremes are notable events.
Typedraws on the price chart
How to add it
Click Indicators (ƒx) in the header.
Search “Bollinger Bands” and click the result.
Hover its legend row and click the gear to open settings.
How traders use it
- Fade the extremes in a range: when price is moving sideways, touches of the upper band are potential sells and touches of the lower band potential buys, ideally confirmed by an oscillator like RSI.
- Trade the squeeze: an unusually narrow band width signals compressed volatility, and a decisive close outside the bands after a squeeze often starts a strong directional move.
- Ride band walks: in strong trends price can hug the upper (or lower) band for many bars; treat repeated band touches as trend strength, not automatic reversal signals.
- Use the middle 20 SMA as the pullback line: trending moves frequently retrace to it before continuing.
- Watch W-bottoms and M-tops: a second low that holds inside the lower band while the first pierced it is a classic reversal setup.
Inputs
| Input | Type | Default | Range / Options |
|---|---|---|---|
| Symbol | symbol | — | — |
| Length | number | 20 | 1–10000 |
| Mult | number | 2 | 0.001–50 |
| Offset | number | 0 | -10000–10000 |
| MA Type | select | SMA | SMA / EMA / WMA |
Plots & styling
| Plot | Style | Default color |
|---|---|---|
| Upper | line | #FF6D00 |
| Middle | line | #2196F3 |
| Lower | line | #2196F3 |
Every plot's color, line width and visibility can be changed on the Style tab. Precision, price-scale labels and status-line values are configurable at the bottom of the Style tab.
Tips
- Double-click any of its lines to jump straight into the settings dialog.
- Save the configured chart as a study template (Indicators menu) to reapply this exact setup elsewhere.
- Right-click the indicator's line for quick actions — settings, visibility and removal without hunting through menus.
- This indicator accepts another symbol — leave it empty to use the chart's own symbol.
Watch out for
- A band touch alone is not a signal; in trends price can stay pinned to a band far longer than a counter-trend trader can stay solvent.
- The bands describe volatility, not direction, and the 20,2 defaults may need tuning for very fast or very slow instruments.