Bollinger upper band
The upper Bollinger Band sits two standard deviations above the 20-period simple moving average and marks the upper volatility zone of price.
The upper band is one of the three lines of Bollinger Bands: it is computed as the 20-period simple moving average plus two standard deviations of price over the same window. Since standard deviation measures volatility, the band pulls away from the average when the market gets agitated and tightens when it calms down. Statistically, the vast majority of prices stay inside the bands: touching the upper band therefore signals a price that is high relative to its recent norm.
Interpretation: mean reversion or breakout
Touching the upper band is not, by itself, a sell signal. In a rangebound market it often precedes a reversion to the mean; but in a strong uptrend, price can “walk” along the upper band for weeks (band walking), and a close above the band after a band squeeze frequently marks the start of a move. In Screener.Trading, a screener rule can detect assets whose price closes above the upper band, on the timeframe of your choice.
Check the band width before interpreting a touch: after a marked squeeze, a break of the upper band is more likely to start a trend than to be a mere excess.
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- FeatureThe multi-indicator, multi-timeframe screenerCombine technical indicators, timeframes and comparison operators to keep only the assets that match your strategy exactly.
- FeatureAutomated scans: your screeners on autopilotBots watch the market for you: they re-run your screeners at every candle close and e-mail you the moment an asset matches.
- IndicatorBollinger BandsA volatility envelope around a moving average: the bands widen when the market gets busy and tighten when it calms down.
- IndicatorSimple Moving Average (SMA)The oldest and most widely used trend indicator: an average of recent closes that smooths out market noise and acts as a dynamic reference line.
- GlossaryBollinger lower bandThe lower Bollinger Band sits two standard deviations below the 20-period simple moving average and marks the lower volatility zone of price.
- GlossaryTimeframeA timeframe is the duration each candle on a chart represents (from one minute to several months) and sets the horizon of the analysis.
- GuideBuilding your first screener, step by stepHow to turn a strategy idea into objective rules, pick the right asset universe, read scan results and iterate until you get a genuinely actionable list of opportunities.