# STARC Bands A Volatility concept (Band & channel systems) in the LuxAlgo Library, with 1 indicator implementation. ## What are STARC Bands? STARC bands (Stoller Average Range Channels, developed by Manning Stoller) are a volatility channel: a simple moving average with upper and lower bands offset by a multiple of the [average true range](https://www.luxalgo.com/library/concept/atr/). Published parameters vary by source; a short centerline of five or six bars with bands about two ATRs away is a common form. Because the offset comes from true range rather than the standard deviation behind [Bollinger Bands](https://www.luxalgo.com/library/concept/bollinger-bands/), the channel tracks realized range directly, widening in fast markets and tightening in quiet ones. Manning Stoller developed the channels in the 1980s, and they circulated through the futures and commodities community before appearing as a built-in study on charting platforms. Stoller's framing was about risk rather than signals: with price pressed against the upper band, a new long is entered at a level already stretched relative to recent average range, so the band argues for taking profits or hunting countertrend setups, with mirror-image logic at the lower band. In construction the bands sit closest to [Keltner channels](https://www.luxalgo.com/library/concept/keltner-channels/); the practical differences are the shorter centerline and the explicitly contrarian reading. The input choice is worth noticing. True range includes gaps, so the bands respond to overnight jumps that close-to-close statistics understate, which mattered in the futures markets where the tool grew up. Width itself is information: expanding bands mark [range expansion](https://www.luxalgo.com/library/concept/range-expansion-contraction/), contracting bands mark the quiet spells hunted by squeeze tools such as the [TTM Squeeze](https://www.luxalgo.com/library/concept/ttm-squeeze/), and comparing current width to its own history amounts to a [volatility percentile](https://www.luxalgo.com/library/concept/volatility-percentile-rank/) read. ## How to identify STARC bands on a chart The channel is plotted directly; identification is mostly about reading position and width. 1. Plot a short simple moving average (five or six bars in the classic form) with bands offset above and below by roughly two ATRs; many platforms ship this as a STARC or ATR-channel study. 2. Locate price within the channel: near the centerline is neutral, pressed against a band is stretched relative to recent average range. 3. Watch how touches resolve: single tags that reject back toward the centerline suggest rotation, while repeated closes hugging one band signal a trend strong enough to keep paying the stretch. 4. Track width over time: widening bands confirm a volatility regime shift, narrowing bands warn that the next move may be a compression break rather than a rotation. ## How it's calculated Volatility bands that wrap a short simple moving average at offsets of a multiple of the Average True Range. ``` TR_t = max(H_t - L_t, abs(H_t - C_{t-1}), abs(L_t - C_{t-1})) ATR_t = (ATR_{t-1} × (m - 1) + TR_t) / m Middle_t = SMA_n(C) Upper_t = Middle_t + k × ATR_t Lower_t = Middle_t - k × ATR_t H_t: high of bar t L_t: low of bar t C: closing price series; C_{t-1} is the prior bar's close t: bar index TR_t: true range of bar t ATR_t: Average True Range, Wilder smoothed; ATR_{t-1} is the prior value and the series is seeded with an m-bar simple average of TR m: ATR length (commonly 15) SMA_n(C): simple moving average of closes over n bars n: moving average length (commonly 5 to 10, often 6) k: ATR multiplier (default 2) Middle_t: center line Upper_t: upper band, also written STARC Band+ Lower_t: lower band, also written STARC Band- ``` STARC stands for Stoller Average Range Channels, developed by Manning Stoller. Defaults vary by platform: SMA lengths of 5 to 10, ATR lengths of 7 to 15, and multipliers near 2 are all common. Band width is driven by ATR rather than standard deviation, which distinguishes STARC bands from Bollinger Bands. ## How traders use it - As entry-risk zones: near the upper band, fresh longs are stretched by construction, so trend traders wait for a rotation back toward the centerline instead of chasing. - As mean-reversion fades in ranging conditions: a band touch paired with a reversal trigger, accepting that strong trends can ride a band for many bars. - As volatility-aware exits: the centerline or opposite band as a trailing reference that adapts to current range instead of a fixed distance. - As a sizing input: because band distance is denominated in ATR, the channel doubles as a position-sizing reference, with stops placed beyond the opposite band or at an ATR multiple so risk scales with conditions. - As an oscillator overlay: the same construction applied to an indicator instead of price, as in the library's STARC-bands-on-RSI study, flagging oscillator readings stretched relative to their own recent range as a reversal warning. ## STARC bands vs. other volatility channels - **Keltner Channels** (https://www.luxalgo.com/library/concept/keltner-channels/): Structural siblings: both offset a moving average by an ATR multiple. Modern Keltner channels center on a longer EMA and are commonly read trend-following; STARC bands use a shorter SMA and were framed as zones that argue against entering at the band. - **Bollinger Bands** (https://www.luxalgo.com/library/concept/bollinger-bands/): Bollinger Bands offset by the standard deviation of closes, so gap-heavy movement can register differently; ATR-based STARC bands count the gaps. Bollinger extremes are also often read as breakout confirmation, the opposite of Stoller's contrarian framing. - **ATR Bands** (https://www.luxalgo.com/library/concept/atr-bands/): Generic ATR bands are the same recipe with free parameters, often centered on price or a longer average. STARC names Stoller's specific short-average variant and its risk-zone interpretation. - **Donchian Channels** (https://www.luxalgo.com/library/concept/donchian-channels/): Donchian channels mark the window's highest high and lowest low, levels price actually set; STARC bands float around an average at an ATR offset and are routinely tagged and exceeded, which is exactly the stretch condition they exist to flag. ## FAQ ### What is the difference between STARC bands and Keltner channels? Structurally they are siblings: both offset a moving average by a multiple of average true range. Typical usage differs. Modern Keltner channels center on a longer EMA and are often read in a trend-following way, while STARC bands traditionally use a shorter simple moving average and were framed by Stoller as risk zones that argue against entering at the band. ### Are STARC band touches reversal signals? Not by themselves. The bands mark prices stretched relative to recent average range, and in a strong trend price can hug one band for many bars while the channel simply expands with volatility. A touch is better read as a warning that entries in that direction carry elevated risk; traders who want reversals pair it with a confirming trigger such as a rejection bar or momentum divergence. ### What does STARC stand for? Stoller Average Range Channel, after developer Manning Stoller. The acronym already contains "channel", so "STARC bands" is technically redundant, but it is the name that stuck on charting platforms. ### What are the standard settings for STARC bands? Commonly a five- or six-bar simple moving average with bands around two ATRs away, though published sources differ and platforms expose all three knobs: average length, ATR length, and multiplier. Wider multipliers are sometimes layered on as an outer extreme, mirroring how [double Bollinger zones](https://www.luxalgo.com/library/concept/double-bollinger-zones/) stack thresholds. ### Are STARC bands better than Bollinger Bands? Neither dominates; they measure different things. ATR-based bands react to true range including gaps, and their width tracks [realized volatility](https://www.luxalgo.com/library/concept/realized-volatility/) in range terms; standard-deviation bands react to how closes scatter around the mean, which powers statistics like [BandWidth](https://www.luxalgo.com/library/concept/bandwidth/) and %B. Many traders run one of each family and pay attention when they disagree. ### Do STARC bands work on intraday charts? Yes; the construction is timeframe-agnostic. Intraday, the session's rhythm shows up in ATR, with wider bands around opens and narrower ones in lulls, so many traders weight a band touch near a volatile open differently from the same touch in quiet conditions. Some require a preceding [volatility contraction pattern](https://www.luxalgo.com/library/concept/volatility-contraction-pattern/) before fading a touch, so they fade rotation rather than ignition. ## Implementations in the Library - STARC Bands (LuxAlgo): https://www.luxalgo.com/library/indicator/starc-bands/ ## Related concepts - Donchian Channels: https://www.luxalgo.com/library/concept/donchian-channels/ - Envelope: https://www.luxalgo.com/library/concept/envelope/ - Bollinger Bands: https://www.luxalgo.com/library/concept/bollinger-bands/ - %B: https://www.luxalgo.com/library/concept/percent-b/ - BandWidth: https://www.luxalgo.com/library/concept/bandwidth/ - Bollinger Squeeze: https://www.luxalgo.com/library/concept/bollinger-squeeze/ - Band Walk: https://www.luxalgo.com/library/concept/band-walk/ - Bollinger Band Tag Reversion: https://www.luxalgo.com/library/concept/bollinger-band-tag-reversion/ - Double Bollinger Zones: https://www.luxalgo.com/library/concept/double-bollinger-zones/ - Fibonacci Bollinger Bands: https://www.luxalgo.com/library/concept/fibonacci-bollinger-bands/ --- Source: https://www.luxalgo.com/library/concept/starc-bands/ (LuxAlgo Library, the encyclopedia of trading & technical analysis). Free to use with attribution: https://www.luxalgo.com/library/license/