# No-demand / No-supply Bars No-demand / No-supply Bars is an indicator on [Vela](https://vela.luxalgo.com/chart), our next-generation charting platform, written in Pine Script®. Tags VSA no-demand and no-supply bars as they complete: an up or down close on a spread below the 20-bar average with volume under both prior bars. A 50-period EMA background filter qualifies each detection against trend context, out-of-context prints can be shown as faded ghost tags, and triangles mark the next-bar confirmations VSA waits for before acting. - Indicator in the LuxAlgo Library, by LuxAlgo, published May 14, 2026. - Access: free. - Concepts: [No-demand / No-supply Bars](https://www.luxalgo.com/library/concept/no-demand-no-supply-bars/) (primary), [Volume Spread Analysis](https://www.luxalgo.com/library/concept/volume-spread-analysis/) - Open on Vela: https://vela.luxalgo.com/chart?pineScriptCodeId=o3366i4gqpslucvzl5jwruaa - Page: https://www.luxalgo.com/library/indicator/no-demand-no-supply-bars/ **No-demand / No-supply Bars** detects the two classic absence findings of Volume Spread Analysis and grades every print against its background. A [no-demand or no-supply bar](https://www.luxalgo.com/library/concept/no-demand-no-supply-bars/) is an up or down close on a narrow spread with volume below both prior bars, a move that professional interest sat out. Every threshold is explicit: narrowness against a 20-bar average spread, volume against the two preceding prints, and a 50-period EMA background read deciding whether a detection qualifies. Qualified bars get filled ND/NS tags; with ghosting enabled, the rest print as faded ghosts. ## How to Trade the No-demand / No-supply Bars? - **Qualified NS above the context average**: a dip that found no sellers while the background shows strength, the pullback used to time longs. - **Qualified ND below the context average**: a rally nobody chased against background weakness, the move to sell into. - **Confirmation triangles**: an up close after a no-supply bar marks the successful test; a down close after a no-demand bar confirms the weakness. Both fire alerts. - **Ghost tags**: a quiet dip inside a genuine downtrend is normal and proves nothing. The faded marks keep that context visible without polluting the signal set. Each tag's tooltip reports the measured spread and volume ratios behind the print. ## No-demand / No-supply Bars Settings - **Spread Average Length** (default 20): bars in the rolling average spread behind the narrowness test. - **Narrow Spread Threshold** (default 1): fraction of the average spread the bar must stay below; lower demands tighter, rarer prints. - **Background Filter** (default Moving Average Trend): qualify detections against trend context, or accept every detection with None. - **Context Average** (default EMA) with **Length** (default 50): the average family and lookback behind the background read. - Style inputs cover tag size, ghost tags for unqualified detections (off), confirmation triangles (on), the tinted context average (on), and bar coloring (off). ## Frequently Asked Questions ### How do these bars relate to the VSA test bar? A [VSA Test Bar](https://www.luxalgo.com/library/indicator/vsa-test-bar/) is an active probe: a dip into prior supply that recovers, checking whether sellers remain. No-supply is the passive cousin: the same quiet, narrow print without the probe-and-recover shape. ### Why are some tags faded? Those detections printed against the wrong background: no-demand with the close above the context average, or no-supply below it. The build reports them without promoting them to signals; disable ghosting to hide them entirely. ### What does the indicator require? A real volume feed, since both classifications compare volume against the prior two bars, and completed bars: tags settle on the close, never intrabar. ## Related indicators - [VSA Test Bar](https://www.luxalgo.com/library/indicator/vsa-test-bar/) (Volume Spread Analysis): markdown at https://www.luxalgo.com/library/indicator/vsa-test-bar.md - [Stopping Volume](https://www.luxalgo.com/library/indicator/stopping-volume/) (Volume Spread Analysis): markdown at https://www.luxalgo.com/library/indicator/stopping-volume.md - [Climactic Action](https://www.luxalgo.com/library/indicator/climactic-action/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/climactic-action.md - [Strength/weakness Background](https://www.luxalgo.com/library/indicator/strength-weakness-background/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/strength-weakness-background.md - [Value Area Reversion Signals](https://www.luxalgo.com/library/indicator/value-area-reversion-signals/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/value-area-reversion-signals.md - [Structure Volume Profile Setups](https://www.luxalgo.com/library/indicator/structure-volume-profile/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/structure-volume-profile.md - [AMD POC Trade Setup](https://www.luxalgo.com/library/indicator/amd-poc-trade-setup/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/amd-poc-trade-setup.md - [Volume Footprint](https://www.luxalgo.com/library/indicator/volume-footprint/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/volume-footprint.md --- Source: https://www.luxalgo.com/library/indicator/no-demand-no-supply-bars/ (LuxAlgo Library). Free to use with attribution: https://www.luxalgo.com/library/license/