# 80% Rule An intraday Market Profile tool that builds the prior session's value area and runs the classic 80% rule setup: an open outside value, a re-entry, and 60 minutes of acceptance inside. It marks each identification step, fires the rotation signal toward the opposite value area boundary, and tracks the setup's live state and outcome in a status table. - Indicator in the LuxAlgo Library, by LuxAlgo, published Mar 26, 2026. - Access: free. - Concepts: [80% Rule](https://www.luxalgo.com/library/concept/80-percent-rule/) (primary), [Auction Market Theory](https://www.luxalgo.com/library/concept/auction-market-theory/) - Open on Vela: https://vela.luxalgo.com/chart?pineScriptCodeId=vif2q37v30b1w066078tht31 - Page: https://www.luxalgo.com/library/indicator/80-percent-rule/ **80% Rule** mechanizes the [80% rule](https://www.luxalgo.com/library/concept/80-percent-rule/) rotation setup from open to resolution: it builds the prior session's value area, classifies today's open against it, and signals only once price has re-entered the area and held inside for the acceptance time. Each step is marked on the chart and mirrored in a live status table. The value area comes from a 25-row profile of the completed session, expanded around the point of control to 70% of its weight; the 60-minute default clock matches the classic two 30-minute periods of acceptance. ## How to Trade the 80% Rule? - **Open outside value**: a circle marks an open above or beneath the prior value area, the precondition, not yet a signal. - **Re-entry triangle**: price closed back inside and the acceptance clock is running. - **80% Rule label**: acceptance confirmed (bullish after an open below value, bearish after an open above), targeting the opposite boundary, with the prior POC as interim reference. - **Outcome tags**: ✓ marks rotation complete; ✕ marks a rejected re-entry or a stop-out back through the entry side. Run it on a 30-minute or lower timeframe so the clock resolves cleanly, and cross-check the levels against a full [volume profile](https://www.luxalgo.com/library/concept/volume-profile/) when methods disagree. ## 80% Rule Settings - **Value Area %** (default 70): share of the profile weight around the POC that defines value. - **Profile Rows** (default 25): profile resolution; more rows sharpen the levels, fewer smooth them. - **Profile Weighting** (default Volume): or TPO (Time) for symbols without reliable volume. - **Custom Session** (default off): restricts the tool to a session window (default 0930-1600). - **Acceptance Time (Minutes)** (default 60): time closes must hold inside value before the signal fires. - Style toggles cover the value area box, POC line, signal labels, step markers and the status table. ## Frequently Asked Questions ### Does the 80% Rule work on daily charts? No. The setup needs the prior session's intraday profile, so it runs on intraday charts only and the table says so otherwise. A 30-minute or lower timeframe keeps the acceptance clock faithful to the classic timing. ### How is this different from the Auction Failure indicator? This build trades one script (open outside, re-enter, accept, rotate) while the [Auction Failure tool](https://www.luxalgo.com/library/indicator/auction-failure/) watches probes beyond many references all day and classifies how each one dies. ### What does the 80% figure refer to? Folklore shorthand from profile trading for how often the setup is said to rotate: a label, not a statistic this indicator measures or promises. Treat the signal as structured context for a trade whose target and invalidation are known before entry. ## Related indicators - [TPO Profile](https://www.luxalgo.com/library/indicator/tpo-profile/) (Auction Market Theory): markdown at https://www.luxalgo.com/library/indicator/tpo-profile.md - [Balance vs Imbalance](https://www.luxalgo.com/library/indicator/balance-vs-imbalance/) (Auction Market Theory): markdown at https://www.luxalgo.com/library/indicator/balance-vs-imbalance.md - [Initial Balance Breakout Signals](https://www.luxalgo.com/library/indicator/initial-balance-breakout-signals/) (Initial Balance): markdown at https://www.luxalgo.com/library/indicator/initial-balance-breakout-signals.md - [Profile Shape Taxonomy](https://www.luxalgo.com/library/indicator/profile-shape-taxonomy/) (Auction Market Theory): markdown at https://www.luxalgo.com/library/indicator/profile-shape-taxonomy.md - [Auction Failure](https://www.luxalgo.com/library/indicator/auction-failure/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/auction-failure.md - [Value Migration](https://www.luxalgo.com/library/indicator/value-migration/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/value-migration.md - [One-timeframing](https://www.luxalgo.com/library/indicator/one-timeframing/) (Volume & Order Flow): markdown at https://www.luxalgo.com/library/indicator/one-timeframing.md - [Initial Balance Volume Deficit](https://www.luxalgo.com/library/indicator/initial-balance-volume-deficit/) (Initial Balance): markdown at https://www.luxalgo.com/library/indicator/initial-balance-volume-deficit.md --- Source: https://www.luxalgo.com/library/indicator/80-percent-rule/ (LuxAlgo Library). Free to use with attribution: https://www.luxalgo.com/library/license/