The Rate of Change (ROC) indicator measures the percentage change in price over a set number of periods — today's price versus the price N bars ago, as a percent. It oscillates around zero: positive means price is higher than N bars ago (upward momentum), negative means lower. It's momentum in its most stripped-down form.

What ROC shows

ROC reads momentum and acceleration. A rising ROC means the move is speeding up; a falling ROC means it's decelerating, even if price is still rising. The zero line is the pivot: crossing above zero signals upward momentum, below zero downward. Extreme ROC readings flag stretched, fast moves that may be due to slow — a momentum-exhaustion hint.

How to use it

Use ROC for momentum confirmation and divergence. A strong breakout with rising ROC confirms real acceleration (a genuine ignition); a new price high with falling ROC is a momentum divergence warning the move is tiring. As a filter, positive-and-rising ROC supports trend-following; ROC oscillating around zero signals no momentum (chop).

ROC isn't direction — it's speed. A rising price on falling ROC is a car still moving but off the gas.

The limits

ROC is a lagging momentum oscillator — it confirms speed, it doesn't predict turns, and it whipsaws in chop like any oscillator. It's noisy on very fast timeframes. Use it as one confirmation among several — at a level, with the regime — not as a standalone trigger. It answers “is this move accelerating or fading?”, which is a useful question when you've already got a setup at a level.