Average True Range (ATR): How to Measure Volatility

The Average True Range (ATR) is a technical indicator that measures market volatility by calculating the average range of price movement over a set period. It does not tell you direction; it tells you how much a market typically moves. Most traders use a 14-period ATR as the default setting.

How ATR Is Calculated

ATR looks at three values for each period and picks the largest:

• Current high minus current low
• Current high minus previous close (absolute value)
• Current low minus previous close (absolute value)

The indicator then averages these “true ranges” over 14 periods (or whatever lookback you choose). A stock with an ATR of $2.50 on a daily chart means it moves about $2.50 per day on average. A futures contract with an ATR of 20 points tells you that 20-point daily swings are normal.

Using ATR for Stop Loss Placement

One of the most practical uses of ATR is setting your stop loss. Instead of picking an arbitrary dollar amount, you base your stop on what the market actually does.

A common approach: place your stop 1.5x to 2x ATR away from your entry. If the ATR is $1.00, your stop goes $1.50 to $2.00 away. This keeps you from getting stopped out by normal price noise while still protecting your capital.

Tight stops in a high-ATR environment lead to constant stop-outs. Wide stops in a low-ATR environment waste your risk-reward ratio. ATR helps you calibrate.

ATR for Position Sizing

ATR also helps with position sizing. If you risk $100 per trade and the ATR-based stop is $2.00, you trade 50 shares. If the ATR-based stop is $5.00, you trade 20 shares. This keeps your dollar risk consistent even when volatility changes.

Many prop firm traders use ATR-based sizing to stay within drawdown limits. When ATR expands, they trade smaller. When it contracts, they can size up. This approach adapts automatically to market conditions.

Reading ATR on Your Charts

ATR appears as a single line below your price chart. Rising ATR means volatility is increasing. Falling ATR means the market is quieting down. Extremely low ATR readings often precede big breakouts, making it a useful tool for breakout trading.

Key Takeaways

• ATR measures how much a market moves on average, not which direction
• Use 1.5x to 2x ATR for stop loss placement to avoid noise-based stop-outs
• ATR-based position sizing keeps dollar risk consistent across different volatility environments
• Low ATR readings often signal a big move is coming
• The 14-period setting works well for most traders and timeframes

Frequently Asked Questions

What is a good ATR value? There is no universally “good” ATR. The number depends on the instrument and timeframe. What matters is whether ATR is high or low relative to its own recent history for that specific market.

Does ATR work on all timeframes? Yes. ATR works on 1-minute charts, daily charts, and everything in between. Just remember that ATR on a 5-minute chart measures average 5-minute ranges, while daily ATR measures average daily ranges.

Can ATR predict market direction? No. ATR only measures the magnitude of price movement, not the direction. You need other tools like moving averages or RSI for directional analysis.

Risk Disclaimer: Trading involves substantial risk of loss. Past performance is not indicative of future results. See our full risk disclaimer.