Indicators · Volatility · live Bitcoin example
Bollinger Bands explained: the squeeze, the bands and what they mean
Bollinger Bands draw a stretchy tube around the price. When the market is calm, the tube gets thin. When the market goes wild, it gets wide. They show you what a “normal” move looks like right now – and when the price is doing something unusual.
What Bitcoin’s Bollinger Bands say right now
Worked out from real Bitcoin candles and refreshed every 30 minutes. It describes what already happened – not what will happen next.
Bollinger Bands on the live Bitcoin chart
The live Bitcoin chart with only Bollinger Bands on. The two pink lines are the upper and lower bands. The middle line (a 20-candle average) is not drawn, but it sits halfway between them.
What are Bollinger Bands?
Bollinger Bands are three lines. The middle band is a simple 20-period moving average. The upper band is that average plus two “standard deviations”. The lower band is the average minus two standard deviations.
A standard deviation is a way to measure how spread out numbers are. If the last 20 closes were all close to each other, the standard deviation is small and the bands sit tight around the price. If the closes were all over the place, it is large and the bands spread out.
So the bands are not fixed price levels. They move every day and adapt to the market. That is their whole point: what is “a big move” for a calm currency pair is tiny for Bitcoin, and the bands adjust automatically.
Most of the time the price stays inside the bands. A close outside is unusual – it tells you the last move was big compared with the last 20 candles. Unusual does not mean wrong, and it does not mean the move must reverse.
Where it comes from: John Bollinger, an American trader and analyst, created the bands in the early 1980s and later wrote the book “Bollinger on Bollinger Bands” (2001). He also created two helper tools – %B and BandWidth – which we show in the live box below.
How Bollinger Bands are calculated
The middle line is easy (an average). The bands need the standard deviation, which sounds scary but is just four little steps.
- MiddleSMA 20The average of the last 20 closes.
- SpreadStandard deviationHow far, on average, the closes are from that average.
- UpperSMA 20 + 2 × deviationThe top of the normal range.
- LowerSMA 20 − 2 × deviationThe bottom of the normal range.
| Closes | 98, 100, 102, 99, 101 |
|---|---|
| Average | 500 ÷ 5 = 100 |
| Distance from the average | −2, 0, +2, −1, +1 |
| Squared and added up | 4 + 0 + 4 + 1 + 1 = 10 |
| Divide by 5, then square root | √2 ≈ 1.41 |
| Upper band = 100 + 2 × 1.41 | 102.83 |
| Lower band = 100 − 2 × 1.41 | 97.17 |
If the next close were 104, it would be above the upper band – an unusually big move compared with those five days. On a real chart the same thing happens with 20 closes, recalculated for every new candle.
How to read Bollinger Bands
The pictures are simple example shapes, so the idea is easy to see. Real charts are messier.
Bollinger Bands squeeze together in a quiet market, then widen when a big move starts. Example drawing, not real data. The squeeze
When the bands get very narrow, the market has been unusually quiet. John Bollinger called this the squeeze. Quiet periods do not last forever, so a squeeze often comes before a bigger move. The squeeze does not tell you the direction – only that energy is building.
In a strong uptrend the price can ride along the upper band for a long time. Example drawing, not real data. Walking the band
In a strong uptrend the price can close near the upper band again and again. This is called walking the band. It shows strength, not weakness – which is why “touching the top band = sell” is a famous mistake.
Back to the middle
In a sideways market price often swings from one band toward the other, and the middle line acts like a magnet. In a trend, the middle line often acts as a floor (uptrend) or ceiling (downtrend) on pullbacks.
Band width
Wide bands mean high volatility – big swings in both directions. After a huge move the bands are very wide, and they often start to narrow as the market calms down again.
Common mistakes beginners make
Almost everyone makes these at first. Knowing them saves a lot of frustration.
- Selling every touch of the upper bandIn a trend, the price can ride the upper band for weeks. A touch means strength, not a top.
- Guessing the squeeze directionA squeeze says a bigger move may come, not which way. Many traders wait for the price to close outside a band first.
- Thinking the bands are support and resistanceThe bands move every candle. They describe volatility, not where buyers or sellers are waiting.
- Ignoring the trendBands work differently in trends and in ranges. Check the middle line’s slope first: flat = range, rising or falling = trend.
Settings most people use
The numbers in brackets you see on charts – explained in plain words.
- Length20 candlesThe average and the deviation use the last 20 closes. This is Bollinger’s standard setting.
- Width2 standard deviationsPuts the bands far enough out that closes outside them are unusual. Some traders use 2.5 for a wider, calmer band.
- Average typeSimple (SMA)The original uses a simple average, so the bands match the deviation, which is also calculated simply.
How to use Bollinger Bands (for beginners)
Six small steps. None of them tells you to buy or sell – they help you read the chart.
- 1Check the widthAre the bands narrow (quiet) or wide (wild)?
- 2Check the middle lineFlat = sideways market. Sloping up or down = trend.
- 3Find the priceNear the top, the middle or the bottom band? Inside or outside?
- 4Spot a squeezeVery narrow bands after a long quiet spell mean energy is building.
- 5Wait for the closeA wick outside the band during the day is not the same as a close outside it.
- 6Add momentumCombine with RSI or volume to see whether a band break has real power.
See Bollinger Bands on other markets
Indicators work the same way on crypto, gold, currencies and stocks. Open any live Kumo chart and press the button.
Learn next
These go well together with this lesson.
Bollinger Bands FAQ
What are Bollinger Bands in simple terms?
A moving average with two lines around it that show the normal price range. The lines get closer when the market is calm and move apart when it gets volatile.
What does it mean when price touches the upper Bollinger Band?
That the price moved up unusually strongly compared with the last 20 candles. In a trend this can happen many times in a row. It is not a sell signal on its own.
What is a Bollinger Band squeeze?
A period when the bands are much narrower than usual, because the market has been very quiet. It is often followed by a larger move, but the squeeze does not tell you which direction.
What are the best Bollinger Band settings?
The standard 20 periods and 2 standard deviations work for most markets and time frames. Changing them makes your chart different from what most traders are looking at.
Can you use Bollinger Bands for crypto?
Yes. Crypto is very volatile, so the bands are often wide. The squeeze is especially watched on Bitcoin, where quiet weeks have often been followed by sharp moves.
Who invented Bollinger Bands?
John Bollinger, in the early 1980s. The name is a registered trademark of his.
All indicator lessons
Free, plain-word lessons, each with a live Bitcoin example.
- Support and resistanceThe price “floors” and “ceilings” where buyers or sellers stepped in before.
- Moving averages (SMA vs EMA)A smooth line through the price that shows which way the trend is going.
- RSIA 0–100 score of how hard a market has been bought or sold lately.
- VolumeHow much was traded – it tells you how many people stand behind a move.
- EMA 200The famous long-term trend line: above it the big picture is up, below it down.
- MACDTwo averages chasing each other – it shows when a move speeds up or slows down.
- Stochastic oscillatorWhere today’s price sits inside its recent high–low range, from 0 to 100.
- Ichimoku cloudThe Japanese “cloud” chart – Kumo’s namesake – showing trend, levels and momentum at once.
Written by
Alex Wu
Crypto, DeFi, perps and FX · driven by data
Alex designed the Kumocast model behind these signals, sets its rules, reviews its accuracy record and updates the methodology whenever the model changes. Signals are refreshed every 30 minutes with live market data.