## Average True Range — ATR Definition

## What is Average True Range — ATR?

The average true range (ATR) is a technical analysis indicator that measures market volatility by decomposing the entire range of an asset price for that period. Specifically, ATR is a measure of volatility introduced by market technician J. Welles Wilder Jr. in his book, «New Concepts in Technical Trading Systems.»

The true range indicator is taken as the greatest of the following: current high less the current low; the absolute value of the current high less the previous close; and the absolute value of the current low less the previous close. The average true range is then a moving average, generally using 14 days, of the true ranges.

### Key Takeaways

- Average true range (ATR) is a technical indicator measuring market volatility.
- It is typically derived from the 14-day moving average of a series of true range indicators.
- It was originally developed for use in commodities markets but has since been applied to all types of securities.

#### Calculating Volatility with Average True Range

## The Formula For ATR Is

The first step in calculating ATR is to find a series of true range values for a security. The price range of an asset for a given trading day is simply its high minus its low. Meanwhile, the true range is more encompassing and is defined as:

## How To Calculate ATR

Traders can use shorter periods than 14 days to generate more trading signals, while longer periods have a higher probability to generate less trading signals. For example, assume a short-term trader only wishes to analyze the volatility of a stock over a period of five trading days. Therefore, the trader could calculate the five-day ATR. Assuming the historical price data is arranged in reverse chronological order, the trader finds the maximum of the absolute value of the current high minus the current low, absolute value of the current high minus the previous close and the absolute value of the current low minus the previous close. These calculations of the true range are done for the five most recent trading days and are then averaged to calculate the first value of the five-day ATR.

## What Does Average True Range Tell You?

Wilder originally developed the average true range (ATR) for commodities, but the indicator can also be used for stocks and indices. Simply put, a stock experiencing a high level of volatility has a higher ATR, and a low volatility stock has a lower ATR. The ATR may be used by market technicians to enter and exit trades, and it is a useful tool to add to a trading system. It was created to allow traders to more accurately measure the daily volatility of an asset by using simple calculations. The indicator does not indicate the price direction; rather it is used primarily to measure volatility caused by gaps and limit up or down moves. The ATR is fairly simple to calculate and only needs historical price data.

The use of the ATR is commonly used as an exit method that can be applied no matter how the entry decision is made. One popular technique is known as the «chandelier exit» and was developed by Chuck LeBeau. The chandelier exit places a trailing stop under the highest high the stock reached since you entered the trade. The distance between the highest high and the stop level is defined as some multiple times the ATR. For example, we can subtract three times the value of the ATR from the highest high since we entered the trade.

Average true range can also give a trader an indication of what size trade to put on in derivatives markets. It is possible to use the ATR approach to position sizing that accounts for an individual trader’s own willingness to accept risk as well as the volatility of the underlying market. (*For a detailed example on how to use ATR for this purpose, read our article, Sizing A Futures Trade Using Average True Range*.)

## Example Of How To Use ATR

As a hypothetical example, assume the first value of the five-day ATR is calculated at 1.41 and the sixth day has a true range of 1.09. The sequential ATR value could be estimated by multiplying the previous value of the ATR by the number of days less one, and then adding the true range for the current period to the product. Next, divide the sum by the selected timeframe. For example, the second value of the ATR is estimated to be 1.35, or (1.41 * (5 — 1) + (1.09)) / 5. The formula could then be repeated over the entire time period.

## Limitations Of ATR

There are two main limitations to using the average true range indicator. The first is that ATR is a subjective measure — meaning that it is open to interpretation. There is no single ATR value that will tell you with any certainty that a trend is about to reverse or not. Instead, ATR readings should always be compared against earlier readings to get a feel of a trend’s strength or weakness.

Second, ATR also only measures volatility and not the direction of an asset’s price. This can sometimes result in mixed signals, particularly when markets are experiencing pivots or when trends are at turning points. For instance, a sudden increase in the ATR following a large move counter to the prevailing trend may lead some traders think the ATR is confirming the old trend; however, this may not actually be the case.

## Average True Range (ATR)

### Table of Contents

## Average True Range (ATR)

## Introduction

Developed by J. Welles Wilder, the Average True Range (ATR) is an indicator that measures volatility. As with most of his indicators, Wilder designed ATR with commodities and daily prices in mind. Commodities are frequently more volatile than stocks. They were are often subject to gaps and limit moves, which occur when a commodity opens up or down its maximum allowed move for the session. A volatility formula based only on the high-low range would fail to capture volatility from gap or limit moves. Wilder created Average True Range to capture this “missing” volatility. It is important to remember that ATR does not provide an indication of price direction, just volatility.

Wilder features ATR in his 1978 book, *New Concepts in Technical Trading Systems*. This book also includes the Parabolic SAR, RSI and the Directional Movement Concept (ADX). Despite being developed before the computer age, Wilder’s indicators have stood the test of time and remain extremely popular.

## True Range

Wilder started with a concept called **True Range (TR)**, which is defined as the greatest of the following:

Absolute values are used to ensure positive numbers. After all, Wilder was interested in measuring the distance between two points, not the direction. If the current period’s high is above the prior period’s high and the low is below the prior period’s low, then the current period’s high-low range will be used as the True Range. This is an outside day that would use Method 1 to calculate the TR. This is pretty straightforward. Methods 2 and 3 are used when there is a gap or an inside day. A gap occurs when the previous close is greater than the current high (signaling a potential gap down or limit move) or the previous close is lower than the current low (signaling a potential gap up or limit move). The image below shows examples of when methods 2 and 3 are appropriate.

Example A: A small high/low range formed after a gap up. The TR equals the absolute value of the difference between the current high and the previous close.

Example B: A small high/low range formed after a gap down. The TR equals the absolute value of the difference between the current low and the previous close.

Example C: Even though the current close is within the previous high/low range, the current high/low range is quite small. In fact, it is smaller than the absolute value of the difference between the current high and the previous close, which is used to value the TR.

## Calculation

Typically, the Average True Range (ATR) is based on 14 periods and can be calculated on an intraday, daily, weekly or monthly basis. For this example, the ATR will be based on daily data. Because there must be a beginning, the first TR value is simply the High minus the Low, and the first 14-day ATR is the average of the daily TR values for the last 14 days. After that, Wilder sought to smooth the data by incorporating the previous period’s ATR value.

Click here for an Excel Spreadsheet showing the start of an ATR calculation for QQQ.

In the spreadsheet example, the first True Range value (.91) equals the High minus the Low (yellow cells). The first 14-day ATR value (.56) was calculated by finding the average of the first 14 True Range values (blue cell). Subsequent ATR values were smoothed using the formula above. The spreadsheet values correspond with the yellow area on the chart below; notice how ATR surged as QQQ plunged in May with many long candlesticks.

For those trying this at home, a few caveats apply. First, just like with Exponential Moving Averages (EMAs), ATR values depend on how far back you begin your calculations. The first True Range value is simply the current High minus the current Low and the first ATR is an average of the first 14 True Range values. The real ATR formula does not kick in until day 15. Even so, the remnants of these first two calculations “linger” to slightly affect subsequent ATR values. Spreadsheet values for a small subset of data may not match exactly with what is seen on the price chart. Decimal rounding can also slightly affect ATR values. On our charts, we calculate back at least 250 periods (typically much further), to ensure a much greater degree of accuracy for our ATR values.

## Absolute ATR

ATR is based on the True Range, which uses absolute price changes. As such, ATR reflects volatility as absolute level. In other words, ATR is not shown as a percentage of the current close. This means low-priced stocks will have lower ATR values than high price stocks. For example, a $20-30 security will have much lower ATR values than a $200-300 security. Because of this, ATR values are not comparable. Even large price movements for a single security, such as a decline from 70 to 20, can make long-term ATR comparisons impractical. Chart 4 shows Google with double-digit ATR values and chart 5 shows Microsoft with ATR values below 1. Despite different values, their ATR lines have similar shapes.

## Conclusion

ATR is not a directional indicator like MACD or RSI, but rather a unique volatility indicator that reflects the degree of interest or disinterest in a move. Strong moves, in either direction, are often accompanied by large ranges, or large True Ranges. This is especially true at the beginning of a move. Uninspiring moves can be accompanied by relatively narrow ranges. As such, ATR can be used to validate the enthusiasm behind a move or breakout. A bullish reversal with an increase in ATR would show strong buying pressure and reinforce the reversal. A bearish support break with an increase in ATR would show strong selling pressure and reinforce the support break.

## Using with SharpCharts

Listed as “Average True Range,” ATR is on the Indicators drop-down menu. The “parameters” box to the right of the indicator contains the default value, 14, for the number of periods used to smooth the data. To adjust the period setting, highlight the default value and enter a new setting. In his work, Wilder often used an 8-period ATR. SharpCharts also allows users to position the indicator above, below or behind the price plot. A moving average can be added to identify upturns or downturns in ATR. Click “advanced options” to add a moving average as an indicator overlay. Click here for a live example of ATR.

## Suggested Scans

### Weeding Out High Volatility

The Average True Range indicator can be used in scans to weed out securities with extremely high volatility. This simple scan searches for S&P 600 stocks that are in an uptrend. The final scan clause excludes high volatility stocks from the results. Note that the ATR is converted to a percentage of sorts so that the ATR of different stocks can be compared on the same scale.

For more details on the syntax to use for ATR scans, please see our Scanning Indicator Reference in the Support Center.

## Additional Resources

### Stocks & Commodities Magazine Articles

**Which Volatility Measure? by Gordon Gustafson**

May 2001 — Stocks & Commodities V. 19:6 (46-50)

## Average True Range (ATR)

## Indicators and Strategies

### Average True Range (ATR)

The Average True Range (ATR) is a tool used in technical analysis to measure volatility. Unlike many of today’s popular indicators, the ATR is not used to indicate the direction of price. Rather, it is a metric used solely to measure volatility, especially volatility caused by price gaps or limit moves.

Read more about the Average True Range in TradingView wiki.

Played around with Lazy Bear’s VMA and Gunazzi’s SuperTrend Cloud . It plots an uptrend if the low of a candle gets above the recent downtrend and plots a downtrend if the high of a candle gets below the recent uptrend, you.

ATR (Average True Range) by Sylvain Vervoort In contrast to other ATR indicators, the line changes color when profits start A diferencia de otros indicadores ATR, la linea cambia de color cunado empezamos a tomas ganancias

Adapted ATR that i am using in BTC 15M charts. It is an usual ATR-Stop smoothed by a VWAP and a VWMA. This crazy config i am using only for BTC, but i found others configs with others assets, like brlusd contracts. You can turn off the barcolor function and change the lenght of the VWAP and VWMA.

The original problem: The choppiness index is great at finding ranging markets, but it is sometimes very slow, which means most of the time it only catches the end of a trend. This indicator tries to solve this. It uses the choppiness index and filters it using a factor that is based on the standard deviation of the ATR. The ATR based filter is calculated by.