intermediatePremiumTechnical Analysis

RSI

The Relative Strength Index (RSI) is a momentum oscillator that measures the speed and size of recent price changes on a 0–100 scale. This article explains what RSI actually measures, the meaning (and frequent misuse) of the 70/30 overbought and oversold thresholds, the centreline at 50, and RSI divergence — where momentum and price disagree. It is emphatic that overbought is not a sell instruction and oversold is not a buy one: in strong trends RSI can stay pinned at an extreme for a long time.

13 min readPublished 19 June 2026

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