A rising ATR says recent moves have genuinely gotten bigger — it never says which way the next one is headed. Its real job is sizing stops, not predicting turns.
J. Welles Wilder Jr. introduced ATR in the same 1978 book as RSI, solving a specific flaw in the plain daily high-minus-low range.
A plain high-minus-low ignores overnight gaps — Wilder's "true range" folds the gap in, so ATR reflects real volatility, gaps included.
Traders adopted ATR as the standard way to size stops and position size relative to actual volatility, across wildly different instruments.
Despite decades of use, it's still frequently misread as hinting at direction — it never has, and never will.
True range takes the largest of: high minus low, high minus yesterday's close, or yesterday's close minus low — then smooths that over a lookback period.
ATR treats up-moves and down-moves identically — it can spike just as easily during a sharp crash as during a sharp rally, saying nothing at all about which one is happening.
A stop set at a multiple of ATR adapts to actual volatility, so risk per trade stays consistent whether the market is calm or wild.
During that crash, ATR spiked to some of its highest readings in years — driven entirely by a sharp decline, proving the indicator's silence on direction.
Weeks later, ATR remained similarly elevated during the sharp recovery rally — the identical reading, this time describing the opposite direction.
ATR has doubled over the past two weeks. A trader concludes price must be about to break out to the upside. Sound?
A trader uses a fixed $1 stop on every stock they trade, regardless of how volatile each one is. What's the likely problem?
A trader computes true range using only today's high minus low, ignoring a large gap up from yesterday's close. Is that a complete measure?
Price and ATR, watched tick by tick on the left — and the mark it leaves in the ledger on the right. A genuine volatility spike on a rally, the same spike on a crash — and a stop sized correctly by ATR.
A stop is placed at a fixed distance from entry. Judge whether it respects the instrument's actual ATR — then call it: sized correctly, or too tight for this volatility.
The classic error is reading a volatility spike as a directional clue. The discipline is mechanical: use ATR only to size stops and position risk, then rely on a genuinely directional tool for the "which way" question entirely.
Wilder built a tool that measures genuine movement, gaps included, and nothing more. Let it size your stops and your risk — never let it whisper a direction it was never built to know.
Give me a lever long enough, and I shall move the world.