# Ascending Base Ascending Base is an indicator on [Vela](https://vela.luxalgo.com/chart), our next-generation charting platform, written in Pine Script®. Detects the O'Neil-style ascending base mechanically: three pullbacks of 10-20% with rising highs and lows over 40-85 bars, formed above a 50-period trend average. It outlines the structure with per-pullback depths, prints the buy level at the third-pullback high, demands 1.4x average volume on the breakout, and tracks a 7% stop after confirmation. - Indicator in the LuxAlgo Library, by LuxAlgo, published Jul 28, 2026. - Access: free. - Concepts: [Ascending Base](https://www.luxalgo.com/library/concept/ascending-base/) (primary) - Open on Vela: https://vela.luxalgo.com/chart?pineScriptCodeId=d62zp1cuwwa76ilzmghtz618 - Page: https://www.luxalgo.com/library/indicator/ascending-base/ **Ascending Base** is the library's first mechanical detector for the [ascending base](https://www.luxalgo.com/library/concept/ascending-base/), the three-pullback growth-stock consolidation: swings confirm with a 5-bar pivot, each pullback must retrace 10–20%, highs and lows must staircase upward, and the base must span 40 to 85 bars. Qualifying bases are outlined with depth labels plus buy and invalidation levels at the third-pullback high and low. Optional filters complete the specification: a 50-period trend filter, 1.4× breakout volume, pullback volume contraction, and a weak-market benchmark check. ## How to Trade the Ascending Base? - **Ascending Base label**: structure confirmed; the buy point is the third-pullback high. - **Breakout**: a close above the buy level on qualifying volume, the entry event, arming the fixed stop. - **Invalidated**: a pre-breakout close below the third-pullback low voids the base. - **Stop Hit**: a post-breakout close below the 7% stop ends the campaign. Bar-count defaults assume daily charts (40–85 bars ≈ eight to seventeen weeks); retune on other timeframes. ## Ascending Base Settings - **Swing Detection Length** (default 5): pivot width; larger returns cleaner swings, later. - **Pullback Depth (%)** (defaults 10 and 20): the required retracement band per pullback. - **Base Duration (bars)** (defaults 40 and 85): allowed span of the base. - **Prior Uptrend Filter** (default on, length 50): the first high must sit above this average. - **Breakout Volume Confirmation** (default on), with **Volume Average Length** (default 50) and **Breakout Volume Multiplier** (default 1.4). - **Pullback Volume Contraction** (default off): pullback legs must average below the baseline. - **Weak Market Filter** (default off, SP:SPX): the benchmark must be lower at the third low than at the start. - **Fixed Stop After Breakout** (default on, 7%): the stop tracked under the buy level. - Style toggles cover the pattern outline, depth labels, and the buy and invalidation levels. ## Frequently Asked Questions ### How does an ascending base differ from a flat base? A [Flat Base](https://www.luxalgo.com/library/indicator/flat-base/) is a tight sideways shelf that corrects through time; the ascending base steps upward, absorbing three 10–20% knockdowns with higher lows each time: a relative-strength pattern, not just a rest. ### Can I run it on symbols without volume data? Yes. Turn off Breakout Volume Confirmation; the structure, depth, duration and trend logic run on price alone. You lose the volume half of the specification, so weigh breakouts accordingly. ### What happens if a new base forms while one is active? A newer valid structure replaces an unresolved one; a base that already resolved on the same third high is not resurrected. Resolved outlines stay as history. ## Related indicators - [O'Neil Base Analysis](https://www.luxalgo.com/library/indicator/oneil-base-analysis/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/oneil-base-analysis.md - [Double-bottom Base](https://www.luxalgo.com/library/indicator/double-bottom-base/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/double-bottom-base.md - [Flat Base](https://www.luxalgo.com/library/indicator/flat-base/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/flat-base.md - [IPO Base](https://www.luxalgo.com/library/indicator/ipo-base/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/ipo-base.md - [Gap Fill Breakouts](https://www.luxalgo.com/library/indicator/gap-fill-breakouts/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/gap-fill-breakouts.md - [On-neck / In-neck / Thrusting](https://www.luxalgo.com/library/indicator/on-neck-in-neck-thrusting/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/on-neck-in-neck-thrusting.md - [Rising/falling Three Methods](https://www.luxalgo.com/library/indicator/rising-falling-three-methods/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/rising-falling-three-methods.md - [Swing Highs/Lows & Candle Patterns](https://www.luxalgo.com/library/indicator/swing-highs-lows-candle-patterns/) (Chart & Candlestick Patterns): markdown at https://www.luxalgo.com/library/indicator/swing-highs-lows-candle-patterns.md --- Source: https://www.luxalgo.com/library/indicator/ascending-base/ (LuxAlgo Library). Free to use with attribution: https://www.luxalgo.com/library/license/