Node reference

Bollinger Bands

A moving average with upper/lower bands set a number of standard deviations away.

Rev. 2026.06

Bollinger Bandsindicator
InputsOutputs
Source
source · number
Bollinger Bands
Middle
middle · number
Upper
upper · number
Lower
lower · number
Configure
period
— Lookback length, in bars
default 20
range 1–500
stdDev
— Band width, in standard deviations
default 2
range 0–10

What it does

Outputs the middle (SMA), upper, and lower bands; band width expands and contracts with volatility.

What happens

Recomputed once per candle from its wired source, incrementally (constant work per bar). It emits no value until the warmup period has passed; after that it produces a value every bar.

When to use

Volatility breakouts (price piercing a band) or mean-reversion back to the middle.

Gotchas

  • Multiple outputs — pick the band you mean.