Aroon indicator
Two lines, Aroon Up and Aroon Down, measuring how many periods have passed since the most recent high and low. Used to spot new trends forming and gauge how mature they are.
What the numbers mean
The lookback counts how many periods have passed since the highest high and the lowest low within that window, scaled to 0–100. A 25-period Aroon Up at 100 means the highest price of the last 25 bars happened today; at 0 it means that high is now 25 bars old.
- 14 — a fast setting, common on intraday and swing charts
- 25 — Chande's original setting, about five weeks of daily bars
- 100 — today produced the highest high (or lowest low) of the whole window
- 70 / 30 — the conventional strong and weak thresholds
- 0 — the extreme is now as old as the window itself
How it is used
Readings above 70 on one line with the other below 30 mark an established trend; both lines low and tangled mark consolidation. Crossings of the two lines are read as the trend changing hands.
- Aroon Up above 70 with Aroon Down below 30 → established uptrend
- Both lines below 50 and tangled → consolidation
- The lines crossing → the trend changing hands
- Aroon Up pinned near 100 for a long stretch → a persistent, orderly advance
How it relates to everything else
Aroon measures the freshness of extremes, where ADX measures the force behind them, so the two answer different halves of the same question: Aroon says how recently a new high was made, ADX says how decisive the move has been. Aroon tends to flag a developing trend earlier and with more false starts.
- Aroon crossover + ADX rising → a new trend with strength behind it
- Aroon tangled below 50 ≈ ADX below 20 — the same range-bound message
- The Aroon Oscillator compresses both lines into one −100 to +100 reading
What to watch for
Because it tracks the age of extremes rather than their size, a single spike can pin a line at 100 while price does nothing. It is a timing measure, not a strength measure.