Most indicators tell you about price direction or momentum. Bollinger Bands tell you something different — they tell you about volatility.
And in crypto — where volatility is the defining characteristic — understanding when volatility is expanding or contracting gives you a powerful edge.
Developed by John Bollinger in the 1980s — Bollinger Bands consist of three lines plotted around price:
Middle Band
A 20-period Simple Moving Average.
The center of the envelope.
Acts as dynamic support/resistance.
Upper Band
Middle band + 2 standard deviations above.
Represents statistically high price — relatively overbought.
Lower Band
Middle band – 2 standard deviations below.
Represents statistically low price — relatively oversold.
Standard deviation measures how much price is deviating from the average. When price is volatile — bands expand. When price is calm — bands contract.
Approximately 95% of all price action occurs within the Bollinger Bands.
This means:
The most powerful signal Bollinger Bands generate:
When bands contract significantly — squeezing together — a big move is coming.
During low volatility periods — bands narrow. Price is consolidating. Energy is building.
When volatility explodes — bands widen rapidly. The direction of the first major candle after the squeeze determines the direction of the move.
Trading the Squeeze:
Real example:
Bitcoin Bollinger Squeeze in September 2023 after months of low volatility. Bands contracted to their tightest in years. Price broke upward — triggering a rally from $26,000 to $73,000 over the following months.
One of the most misunderstood aspects of Bollinger Bands:
Price can walk along the upper or lower band for extended periods.
Upper band walk:
Price consistently touching or hugging the upper band.
This is NOT overbought — it is a sign of STRONG momentum.
Do not sell just because price is at upper band.
Lower band walk:
Price consistently touching or hugging the lower band.
This is NOT a buy signal — it is a sign of STRONG bearish momentum.
Do not buy just because price is at lower band.
Band walks occur in strong trends. Only look for reversals when price stops touching the band and pulls back toward the middle.
In sideways markets — Bollinger Bands excel at mean reversion trading.
Setup:
Price touches lower band + shows reversal signal → buy → target middle band or upper band.
Price touches upper band + shows reversal signal → sell → target middle band or lower band.
Rules for mean reversion:
Band Width measures how far apart the upper and lower bands are.
Narrow band width = low volatility = squeeze forming
Wide band width = high volatility = big move underway
Tracking band width helps identify squeeze setups before they become obvious.
%B shows where price is relative to the bands.
The classic combination:
Bullish setup:
Price touches lower band + RSI below 30 = oversold confirmation.
Strong buy signal in sideways markets.
Bearish setup:
Price touches upper band + RSI above 70 = overbought confirmation.
Strong sell signal in sideways markets.
This combination filters out many false signals from using either indicator alone.
Mistake 1 — Selling at upper band in uptrend
In a strong uptrend price walks the upper band. Selling every touch of upper band results in losing short trades.
Mistake 2 — Buying at lower band in downtrend
Same problem in reverse. Lower band touch in downtrend is a continuation signal — not reversal.
Mistake 3 — Ignoring the squeeze
The squeeze is the most powerful signal Bollinger Bands generate. Many traders focus on band touches and miss the explosive squeeze breakouts.
In the next topic we will move to momentum indicators — starting with RSI — the single most popular indicator among crypto traders.