# VSA Test Bar VSA Test Bar is an indicator on [Vela](https://vela.luxalgo.com/chart), our next-generation charting platform, written in Pine Script®. Marks the VSA test: a narrow, low-volume dip toward or into a recent high-volume supply area that closes firm and holds. Test volume must stay below 0.7x the 20-bar average and half the supply volume by default, with confirmation from an up bar on rising volume within 5 bars. Supply areas, an invalidation line at the test low, failed-test flags and four alerts complete the read. - Indicator in the LuxAlgo Library, by LuxAlgo, published May 22, 2026. - Access: free. - Concepts: [VSA Test Bar](https://www.luxalgo.com/library/concept/vsa-test-bar/) (primary), [Volume Spread Analysis](https://www.luxalgo.com/library/concept/volume-spread-analysis/) - Open on Vela: https://vela.luxalgo.com/chart?pineScriptCodeId=cxbsygujna159mqe8q0pcoks - Page: https://www.luxalgo.com/library/indicator/vsa-test-bar/ **VSA Test Bar** asks the follow-up question of volume spread analysis and grades the market's answer, the first faithful build of the [test bar](https://www.luxalgo.com/library/concept/vsa-test-bar/) as a full detection sequence. High-volume down bars register supply areas; a later dip toward or into that area on narrow spread and clearly low volume, closing firm and holding the area low, prints a Test label with a dashed invalidation line at the test bar's low. ## How to Trade the VSA Test Bar? - **Test**: a probe of prior supply under both volume thresholds, closing at or above the Minimum Close Position. A question posed, not yet an entry. - **Test Confirmed**: an up bar that closes firm on volume above the test bar's own, inside the window; the line turns solid, the area recolors bullish, and the classic stop sits below the test low. - **Test Negated**: no qualifying response in time, or a close below the test low, marked with a small cross. - **Failed Test**: the probe instead draws heavy volume; supply is still present, and the area recolors bearish. It slots into the wider [volume and order-flow family](https://www.luxalgo.com/library/family/volume-orderflow/). ## VSA Test Bar Settings - **Average Length** (default 20): baseline averages for volume and spread. - **Low Volume Threshold** (default 0.7): maximum test volume as a multiple of that average. - **Max Fraction Of Supply Volume** (default 0.5): the test must also print well below the probed area's volume. - **Maximum Spread Multiple** (default 1.0) and **Minimum Close Position %** (default 50): the narrow-spread, firm-close anatomy. - **Supply Bar Volume Multiple** (default 1.5) and **Context Lookback (Bars)** (default 50): what registers as supply and how long it stays valid. - **Confirmation Window (Bars)** (default 5), **Flag Failed Tests** (on) and **Failed Test Volume Multiple** (default 1.5): the response rules. - **Show Supply Area** and **Show Invalidation Line** (both on): the drawings. ## Frequently Asked Questions ### How does a test differ from a no supply bar? A [no supply bar](https://www.luxalgo.com/library/indicator/no-demand-no-supply-bars/) is a single-bar read: a down close printing a narrow bar on shrinking volume, anywhere. The test demands context: prior high-volume supply whose lows held, a probe into that area, and a confirming response. ### Why does the test need prior supply? Low volume on a dip means little in a vacuum. The build demands a recent supply area whose low has held (overlapping supply bars extend one area) and breaks the context the moment a bar closes below the area low. ### Does it work on symbols without volume? No. Volume is the verdict itself, so a symbol reporting none raises an error. Data-window series Relative Volume and Close Position % expose the measurements behind every test. ## Related indicators - [No-demand / No-supply Bars](https://www.luxalgo.com/library/indicator/no-demand-no-supply-bars/) (Volume Spread Analysis): markdown at https://www.luxalgo.com/library/indicator/no-demand-no-supply-bars.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 - [Volume Footprint](https://www.luxalgo.com/library/indicator/volume-footprint/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/volume-footprint.md - [Liquidity Structure & Order Flow](https://www.luxalgo.com/library/indicator/liquidity-structure-order-flow/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/liquidity-structure-order-flow.md - [Volume Delta Candles](https://www.luxalgo.com/library/indicator/volume-delta-candles/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/volume-delta-candles.md - [Liquidity Delta Profiler](https://www.luxalgo.com/library/indicator/liquidity-delta-profiler/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/liquidity-delta-profiler.md --- Source: https://www.luxalgo.com/library/indicator/vsa-test-bar/ (LuxAlgo Library). Free to use with attribution: https://www.luxalgo.com/library/license/