Relative Strength Index (RSI)
A momentum indicator that measures the speed and size of recent price changes on a scale of 0 to 100.
The RSI compares the size of recent gains to recent losses. Readings above 70 are traditionally called 'overbought' and below 30 'oversold' — but these are descriptions of momentum, not buy or sell signals.
In a strong trend, the RSI can stay overbought or oversold for a long time, which is exactly why reading it mechanically can mislead. It is an educational tool, not a recommendation.
Key points
- Momentum gauge on a 0–100 scale.
- Above 70 'overbought', below 30 'oversold'.
- Can stay stretched in strong trends — not a signal.