ATR indicator: what it is and how to use it for stops

What is the ATR indicator and what does it measure?

ATR stands for Average True Range, in Italian «escursione media reale». It is an indicator of volatility, meaning how far a price moves on average in one candle, whether that candle covers an hour, a day or a week. It was invented in 1978 by the American engineer and trader J. Welles Wilder, the same man behind the RSI, and it has been among the most used tools ever since for a simple reason: it answers a question everyone asks before opening a position, “how much room should I give the price?”.

There is only one word to keep in mind: the ATR measures how much, never where. It doesn't tell you whether the price will rise or fall. A high ATR means recent candles have been big, a low ATR that they have been small. That's all, and it's already a lot.

How do you calculate the average true range?

The calculation has two steps. First you find the true range of each candle, that is the largest of three numbers:

1. the distance between the high and the low of the candle;
2. the distance between the high of the candle and the close of the previous candle;
3. the distance between the low of the candle and the close of the previous candle.

The last two numbers exist so you don't miss the gaps: if a stock closes at 100 and opens at 108 the next day, the distance between that day's high and low alone would tell a calmer story than the real one. Then you average the true ranges of the last 14 periods. Wilder used an average that gives slightly more weight to recent data, while some platforms use the simple average, so two charts can show slightly different values. That isn't a mistake: check which of the two your tool uses.

You don't have to do it by hand. Every charting platform has the ATR among its indicators, and you just add it under the and the. What matters is knowing how to read it.

How do you read the ATR on a chart?

You read it as a line rising and falling below the price. If it rises, the market is moving more. If it falls, it is calming down. An illustrative example, with invented numbers: a coin trades at 100 and has a daily ATR of 4. That means that, over the last 14 days, it has covered on average about 4 points from one extreme of the candle to the other, which is 4% of its price.

To compare different coins it helps to look at the ATR as a percentage of the price, because an ATR of 4 on a coin worth 100 and an ATR of 4 on a coin worth 2,000 are two different worlds. The first is jumpy, the second calm. Often periods of great calm, with the ATR falling, come before a wider move, and periods of great agitation tend to wear out, but that is a habit of markets and not a rule: the ATR anticipates nothing, it describes.

How do you use the ATR to choose a stop loss?

It is the most common use and probably the most useful. A stop loss placed “by feel” has two opposite flaws. If it's too close, normal market noise is enough to trigger it and you end up out of an idea that might have been right. If it's too far, the loss on each trade becomes bigger than the one you had decided to accept.

The ATR gives you an objective yardstick. You decide on a multiple, for example one and a half or two times the ATR, and place the stop at that distance from your entry price. With the earlier example, an ATR of 4 and a multiple of 2, the stop sits 8 points below the entry if you are long and 8 above if you are short. The multiple isn't magic. The higher it is, the more room the stop has to breathe and the smaller the position must be. The lower it is, the more often the stop gets hit. You choose it by testing, on a DEMO account, not by copying it from a video.

Then there is a variant that follows the price as it moves in the right direction, the trailing stop, which many traders build around the ATR precisely because it adapts on its own to the volatility of the moment.

How do you calculate position size with the ATR?

Here the ATR becomes an ally of risk management. First you decide how much you are willing to lose if the stop is hit, for example 1% of your capital. Then the stop distance, calculated with the ATR, tells you how many units you can buy. Illustrative example: capital of 5,000, risk of 1% which is 50, stop 8 points from the entry. Divide 50 by 8 and you get about 6 units.

When the coin gets agitated and the ATR doubles, the stop moves further away and the units are halved, so the maximum loss stays what you chose. It is the reasoning of the position sizing, and if you don't want to do the math by hand there is the position size calculator. The ATR doesn't make trading less risky: it makes risk a choice of yours instead of a side effect of the market's mood.

How many periods should you use: 14 or something else?

The 14 is the value Wilder proposed and the default you find almost everywhere. With fewer periods, say 7, the indicator reacts quickly but is jumpy. With more periods, say 21 or 50, it is smoother but arrives late when volatility changes suddenly. There is no absolute right number. To start, stay on 14, on the same timeframe where you open and close your trades, and change it only if you have a written reason and a test done on past data.

What are the limits of the ATR?

There are four, and knowing them spares you some illusions.

1. It gives no direction. A high ATR applies to a crash just as it does to a rally.
2. It is an average, and averages hide extremes. A candle worth three times the ATR happens, and your stop must be able to withstand it or the position must be small enough not to hurt you.
3. It looks backward. After unexpected news, volatility can change in a few minutes, while the ATR with 14 periods notices a few candles late.
4. It doesn't protect against the slippage: if the market gaps, your stop can be executed further away than where you placed it.

This is why the ATR is used together with everything else, not alone: levels such as support and resistance, a risk cap per trade and, when leverage is involved, an eye on the liquidation.

How do you practice using the ATR without risking real money?

In a demo account with real prices you can add the ATR to a coin, calculate the stop with two different multiples and compare, after a few weeks, how many stops were hit by “noise” and what each choice cost. After thirty trades you have an idea of your own, based on your own data. The complete path, from first steps to risk management, is in the guide to mindful online trading.

Where STA fits in

STA works on OKX derivatives: ten artificial intelligence agents analyze the markets twice a day and, before every card, set a Bull against a Bear. Among the data the agents read is the recent volatility of each coin, because without knowing how much a market moves you can't judge whether an idea has room to work. Every card comes with its stop, and the funds stay in your OKX account.

The DEMO is free forever, with real prices and the same cards as REAL. You need an account. During the launch phase, which began on 16 October 2026, STA's fees are temporarily disabled, even in REAL; the ordinary price list, suspended while the launch lasts, is 18% of the positive net result of each day, with no offsetting of losses. The history of the cards, losses included, is public on GitHub.

Frequently asked questions

This article is for information only and is not investment advice. Trading crypto-assets involves a high risk, including the total loss of the capital used. Numerical examples are for illustration.