The default Bollinger Band setting is:

20 periods, 2 deviations. 20 and 2 are the defaults.

In strong trends price can:

Walk along a band. Trends ride the band.

Not a signal alone. Context is needed.

Courses / Volatility and Volume Indicators

Bollinger Bands

A moving average with bands two standard deviations away.

Bollinger Bands plot a 20-period simple moving average with an upper and lower band two standard deviations away. The bands widen when volatility rises and narrow when it falls.

Price tends to stay inside the bands most of the time. Touching a band is not a signal by itself. In trends, price can walk along a band.

Common uses: mean reversion in ranges (fade the bands), and breakouts after a squeeze (see the Bollinger squeeze lesson).

Key takeaways

20 SMA plus and minus 2 standard deviations
Bands widen and narrow with volatility
Band touches are not signals alone

Quiz

The default Bollinger Band setting is: Answer: 20 periods, 2 deviations. 20 and 2 are the defaults.
In strong trends price can: Answer: Walk along a band. Trends ride the band.
A band touch is: Answer: Not a signal alone. Context is needed.

Educational content, not financial advice.