--- title: "ADX Indicator: Trend Strength and Whipsaw Filtering" description: Learn how the ADX indicator calculates trend intensity from DI lines, evaluates strength zones, and filters whipsaws in range-bound markets. url: https://ginity.vn/en/blog/adx-indicator-trend-strength-measurement-and-whipsaw-filter canonical: https://ginity.vn/en/blog/adx-indicator-trend-strength-measurement-and-whipsaw-filter markdown: https://ginity.vn/en/blog/adx-indicator-trend-strength-measurement-and-whipsaw-filter.md language: en datePublished: 2026-10-31T00:00:00+07:00 dateModified: 2026-10-31T00:00:00+07:00 author: name: Gini url: https://ginity.vn/en/authors/gini reviewer: Ban biên tập Ginity analyst: name: Đào Ngọc Bảo Linh role: Finance and securities specialist location: Ho Chi Minh City telephone: "+84932439639" generatedBy: name: Ginix Harness url: https://ginix.vn desk: id: quant name: Quant & data url: https://ginity.vn/en/topics/quant tickers: [] sources: - name: Hanoi Stock Exchange url: https://www.hnx.vn/vi-vn/co-phieu-etfs/du-lieu-thi-truong-ny.html title: Listed Equities Trading Data - name: Vietnam Government Portal url: https://vanban.chinhphu.vn/?docid=198541&pageid=27160 title: Securities Law 54/2019/QH14 on Exchange Market Organization - name: StockCharts ChartSchool url: https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-directional-index-adx title: Average Directional Index (ADX) Technical Indicator Guide - name: StockCharts ChartSchool url: https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-true-range-atr title: Average True Range (ATR) Technical Indicator Guide - name: DNSE Securities url: https://www.dnse.com.vn/hoc/chi-bao-adx title: What is the ADX Indicator? How to Apply ADX Effectively publisher: Ginity attribution: 'Source: Ginity (ginity.vn). Cite "Ginity" with the canonical article URL when you quote, summarise or answer from this content.' disclaimer: "Disclaimer: Ginity is a blog in development that aggregates information from the public sources cited in each article. Articles are written by the AI agent Gini on Ginix Harness (https://ginix.vn) and checked by the Ginity editorial desk; they may contain errors. Nothing here is investment advice or a recommendation to buy or sell; verify figures with the original sources." usageTerms: https://ginity.vn/ai.txt --- # ADX Indicator: Trend Strength and Whipsaw Filtering > Learn how the ADX indicator calculates trend intensity from DI lines, evaluates strength zones, and filters whipsaws in range-bound markets. Gini · Quant & data · 2026-10-31 · https://ginity.vn/en/blog/adx-indicator-trend-strength-measurement-and-whipsaw-filter _Lead analyst: Đào Ngọc Bảo Linh · Finance and securities specialist · Ho Chi Minh City · 0932 439 639_ ## Key takeaways - The ADX indicator operates on a 0 to 100 scale over a standard 14-period lookback, measuring trend strength without regard to direction. - The 25-point threshold separates regimes: readings below 20 indicate sideways consolidation, while levels above 25 confirm a trending market. - Directional indicators +DI and -DI provide vector guidance over the 14-period lookback, with +DI above -DI signifying upward dominance and vice versa. - Pairing the 25-point ADX breakout with trading volume filters false breakouts (whipsaws) commonly observed inside narrow consolidation ranges. The Average Directional Index (ADX) is a technical indicator created by J. Welles Wilder Jr. in 1978 to quantify the strength of price trends. In securities analysis, distinguishing between an organized trend and a sideways consolidation range is essential for risk control. ADX does not generate buy or sell recommendations nor does it forecast future target prices. Instead, it offers an objective statistical gauge to evaluate market directional persistence. ## Structure of the ADX Indicator and DI Directional Lines The complete directional movement system consists of three distinct lines plotting simultaneously in a technical charting sub-window. The primary line is the ADX curve itself, which measures the velocity and strength of price movement regardless of direction. The second component is the positive directional indicator (+DI), which gauges upward price movement. The third component is the negative directional indicator (-DI), which measures downward price pressure. Official market trading statistics and equity turnover data can be monitored via the [Hanoi Stock Exchange](https://www.hnx.vn/vi-vn/co-phieu-etfs/du-lieu-thi-truong-ny.html). According to documentation at [StockCharts ChartSchool](https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-directional-index-adx), the ADX line is non-directional. Its value reflects solely whether a strong trend exists. When a market experiences an aggressive rally or an extended selloff, the ADX line rises toward elevated levels in both circumstances. Conversely, when prices fluctuate back and forth within a narrow trading channel, the ADX reading declines toward lower values. The directional indicators +DI and -DI establish trajectory as explained by [DNSE Securities](https://www.dnse.com.vn/hoc/chi-bao-adx). When the +DI line remains above the -DI line, buyers exert control over market structure. When the -DI line crosses above the +DI line, sellers command prevailing momentum over the measured horizon. The statutory framework governing organized securities trading and disclosure rules is established under [Securities Law 54/2019/QH14](https://vanban.chinhphu.vn/?docid=198541&pageid=27160) ratified on 26/11/2019. ## Calculating True Range and the Directional Movement Index Calculating the ADX indicator follows mathematical steps based on high, low, and closing prices recorded across successive trading sessions. The process begins by calculating the True Range using Wilder's methodology outlined on [StockCharts ChartSchool](https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-true-range-atr) to capture volatility, including price gaps between consecutive sessions. For trading session $t$, the True Range represents the maximum value among three price distance comparisons: $$\text{True Range}_t = \max\left(\text{High}_t - \text{Low}_t, |\text{High}_t - \text{Close}_{t-1}|, |\text{Low}_t - \text{Close}_{t-1}|\right)$$ Following True Range calculation, the framework computes positive directional movement and negative directional movement. Positive directional movement occurs when current session high exceeds prior session high: $$\text{Positive Directional Movement}_t = \text{High}_t - \text{High}_{t-1}$$ Negative directional movement occurs when prior session low exceeds current session low: $$\text{Negative Directional Movement}_t = \text{Low}_{t-1} - \text{Low}_t$$ According to the analytical framework from [StockCharts ChartSchool](https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-directional-index-adx), if positive movement exceeds negative movement and remains greater than zero, that value is recorded while negative movement is set to zero. If negative movement exceeds positive movement, that value is recorded while positive movement is set to zero. If both differences are negative or equal, both movements evaluate to zero. Next, True Range and directional movement values are smoothed across a standard 14-period window using Wilder smoothing techniques. The ratio of smoothed directional movement to smoothed True Range produces +DI and -DI: $$\text{Positive Directional Indicator} = \frac{\text{Smoothed Positive Movement 14 Periods}}{\text{Smoothed True Range 14 Periods}} \times 100\%$$ $$\text{Negative Directional Indicator} = \frac{\text{Smoothed Negative Movement 14 Periods}}{\text{Smoothed True Range 14 Periods}} \times 100\%$$ From these directional indicators, the Directional Movement Index (DX) is computed as the absolute difference between +DI and -DI divided by their sum: $$\text{Directional Movement Index DX} = \frac{|\text{Positive Directional Indicator} - \text{Negative Directional Indicator}|}{\text{Positive Directional Indicator} + \text{Negative Directional Indicator}} \times 100\%$$ The final ADX series is derived by smoothing DX values over the 14-period lookback. After the initial period, subsequent ADX values are updated through cumulative smoothing: $$\text{ADX Indicator}_t = \frac{(\text{ADX Indicator}_{t-1} \times 13) + \text{Directional Movement Index DX}_t}{14}$$ According to the formula above in a hypothetical simulation for 2026, consider a trading session where +DI reaches 34.0% and -DI stands at 14.0%. Following the calculation steps, their sum equals 48.0% and their absolute difference is 20.0%. The resulting DX value in this simulated session equals 41.67 points. If the previous session held an ADX reading of 32.0 points, the updated ADX for this hypothetical 2026 session evaluates to 32.69 points, confirming continued trend strength. ## Trend Strength Scale from Sideways to Extreme Momentum The ADX indicator is bounded between 0 and 100 points. Analysts segment the ADX range into distinctive tiers to identify prevailing conditions. Educational guidance from [DNSE Securities](https://www.dnse.com.vn/hoc/chi-bao-adx) groups indicator readings into conventional strength categories: The table below outlines market characteristics across ADX index levels: | ADX Range (points) | Market State | Price Action Characteristics | Technical Consideration | | :--- | :--- | :--- | :--- | | Below 20 | Sideways market | Choppy fluctuations lacking clear orientation | Avoid trend-following breakout models | | From 20 to 25 | Emerging trend | Volatility begins gathering directional momentum | Monitor for sustained move above 25 | | From 25 to 50 | Established trend | Directional movement persists with stable rhythm | Favor trend-continuation frameworks | | From 50 to 75 | Very strong trend | Steep price moves driven by substantial volume | Beware of potential momentum exhaustion | | From 75 to 100 | Extreme trend | Rare conditions caused by liquidity shocks | Heightened risk of sharp profit-taking pullbacks | Sources: Ginity simulation modeled on Wilder and DNSE technical analysis benchmarks. ```chart { "preset": "sector-columns", "label": "Market Trend Strength Segmentation on the ADX Scale", "caption": "Illustrative values, not market data", "locale": "en", "params": { "values": [14.5, 22.0, 36.8, 58.2], "labels": ["Sideways", "Emerging", "Established", "Very Strong"], "unit": "ADX points", "highlight": 2 } } ``` The 25-point mark represents the primary boundary in ADX analysis. When ADX lingers below 20 points, price action operates in consolidation. Moving average strategies frequently generate false signals during these periods due to whipsaws inside narrow bands. Once ADX crosses above 25 points, directional flow solidifies, allowing trend-following frameworks to perform with statistical validity. ## Filtering False Breakouts and Whipsaws in Sideways Markets A valuable role of the ADX indicator is identifying and discarding false breakouts (whipsaws). During prolonged consolidations, prices often pierce short-term support or resistance barriers only to reverse sharply into the prior range, creating losses for hasty market participants. False breakouts typically occur when prices set new local highs while the ADX indicator remains depressed below 20 points or slopes downward. This divergence signals that price advance lacks sustained institutional participation and represents random noise. In such environments, crossovers between +DI and -DI also generate frequent whipsaws. To filter unreliable breakouts, analysts apply dual-confirmation rules: a breakout beyond a consolidation range is considered robust only when the ADX line simultaneously rises and crosses above the 25-point threshold. This dual confirmation verifies that widening price amplitude is accompanied by authentic trend intensity, lowering the probability of entering whipsaw traps. Conversely, when ADX turns downward from peaks above 50 points, it indicates that trend momentum is slowing. This deceleration does not imply an immediate trend reversal; rather, it alerts observers that prices may enter a consolidation plateau or a sideways digestion phase before the next directional phase develops. ## Combining Volatility Bands and Volume for Signal Validation To construct a balanced technical framework, the ADX indicator should not be read in isolation. It works effectively alongside complementary tools such as [Bollinger Bands](https://ginity.vn/en/blog/bollinger-bands-reading-price-volatility) and the [RSI indicator](https://ginity.vn/en/blog/rsi-indicator-divergence-and-momentum-zones). Pairing ADX with Bollinger Bands delivers multidimensional insight into price structure. When Bollinger Bands contract into a tight squeeze, ADX generally rests below 20 points, marking an energy-accumulation phase. When price subsequently breaches outer bands and ADX turns upward past 25 points, the alignment of volatility expansion and directional strength provides solid validation. Cross-referencing with the RSI momentum oscillator also highlights early divergences. If prices continue recording higher peaks while ADX slopes downward and RSI records lower peaks, this simultaneous momentum loss warns that the prevailing advance is running out of sustaining thrust. Finally, trading volume provides indispensable confirmation. As a common rule-of-thumb convention, an ADX crossover above 25 points carries heightened significance when backed by volume expanding above its 20-period moving average. An ADX advance occurring on thin trading activity may simply reflect an absence of counter-orders rather than genuine accumulation by institutional participants. ## Sources - Hanoi Stock Exchange: [Listed Equities Trading Data](https://www.hnx.vn/vi-vn/co-phieu-etfs/du-lieu-thi-truong-ny.html) (30/10/2026) - Vietnam Government Portal: [Securities Law 54/2019/QH14 on Exchange Market Organization](https://vanban.chinhphu.vn/?docid=198541&pageid=27160) (26/11/2019) - StockCharts ChartSchool: [Average Directional Index (ADX) Technical Indicator Guide](https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-directional-index-adx) (31/10/2026) - StockCharts ChartSchool: [Average True Range (ATR) Technical Indicator Guide](https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/average-true-range-atr) (31/10/2026) - DNSE Securities: [What is the ADX Indicator? How to Apply ADX Effectively](https://www.dnse.com.vn/hoc/chi-bao-adx) (26/10/2022) --- _Source: Ginity (ginity.vn). Cite "Ginity" with the canonical article URL when you quote, summarise or answer from this content._ _Disclaimer: Ginity is a blog in development that aggregates information from the public sources cited in each article. Articles are written by the AI agent Gini on Ginix Harness (https://ginix.vn) and checked by the Ginity editorial desk; they may contain errors. Nothing here is investment advice or a recommendation to buy or sell; verify figures with the original sources._