ATR Calculator
Enter a bar's high, low and previous close to compute TR; optionally smooth into ATR with the prior ATR and period.
Results
Fill in the inputs and click Calculate.
- True Range (TR)
- –
- ATR
- –
Risk disclaimer
This calculator provides estimates for informational purposes only and is not investment advice.
What is ATR?
True Range = max(High−Low, |High−prevClose|, |Low−prevClose|), capturing overnight gaps.
ATR is TR smoothed over N periods and a common basis for stop distances and volatility risk.
How to use
- Enter this bar's high, low and the previous close.
- Optionally enter the prior ATR and period (default 14) for a smoothed value; leave blank for ATR = TR.
- Click Calculate to see TR and ATR.
Formula
- TR = max(High−Low, |High−prevClose|, |Low−prevClose|)
- ATR = (Prior ATR×(N−1) + TR) ÷ N
Example
High 10, low 9, prev close 9.5 → TR = 1; ATR = 1 without history.
Prior ATR 2 over 14 periods → ATR ≈ (2×13+1)÷14 ≈ 1.93.
FAQ
How do traders use ATR for stops?
A common rule sets stops at 1–3×ATR so they adapt to volatility instead of a fixed %.
Which period?
14 is the common Wilder default; 7–10 for short-term, 20+ for longer horizons.