What it measures
Bollinger Band Width is most useful when its signal answers a specific question: measure compression and expansion directly. Start with the default settings, then evaluate whether the lookback matches the instrument and timeframe.
How professionals use it
Professional traders use this tool as one layer of evidence. The strongest interpretation comes from aligning the indicator with market structure, location, volatility and volume rather than reacting to a single crossover.
Map trend, range boundaries and major levels before reading the indicator.
State exactly what the indicator must show to support the price thesis.
Use price structure—not the indicator alone—to decide when the idea is wrong.
Settings by trading style
| Style | Starting approach | Trade-off |
|---|---|---|
| Intraday | Use a shorter lookback only after testing. | More responsive, more noise. |
| Swing | Begin near standard defaults. | Balanced responsiveness and stability. |
| Position | Use longer lookbacks and higher-timeframe confirmation. | Smoother but later signals. |
Signal framework
Price structure is constructive and the indicator confirms improving trend, momentum, participation or volatility.
Price structure is weakening and the indicator confirms deterioration rather than creating the thesis by itself.
Conflicting readings usually mean wait, reduce size or use a different tool suited to the regime.
Common mistakes
- Treating one threshold or crossover as an automatic trade.
- Ignoring higher-timeframe structure and nearby liquidity.
- Optimizing settings until they fit historical data perfectly.
- Using multiple indicators that measure the same underlying variable.
- Confusing a useful alert with a complete trading system.
Use the Pine Script
Open TradingView → Pine Editor → create a new indicator → paste the code → Save → Add to chart. Review the inputs and test it on replay or paper trading before relying on it.
//@version=6
indicator("VG Bollinger Band Width", shorttitle="VG BOLLINGER-", overlay=false)
len=input.int(20,"Length")
mult=input.float(2.0,"StdDev")
b=ta.sma(close,len)
d=mult*ta.stdev(close,len)
bw=100*((b+d)-(b-d))/b
plot(bw,"Band Width %",color=color.blue)This educational implementation is not a recommendation and may behave differently across symbols, sessions and timeframes. It does not promise profitability.