The RSI (its full name is the Relative Strength Index, though you never need to remember that) works like a speedometer for price. It runs from 0 to 100 and answers a single question: has price been pushed too far, too fast in one direction?
When it climbs above about 70, the asset is said to be overbought โ it has been racing upward and may be due a pause or a pullback, like a runner who has sprinted and needs to catch their breath. When it drops below about 30, it is oversold โ it has been hammered down hard and may be ready to bounce. It is never a guarantee, just a heads-up that the elastic band is stretched and tension is building.
SeerSignals actually runs two versions side by side: a slow, steady one (RSI-14) that filters out the noise and gives a calmer read, and a fast, twitchy one (RSI-3) that catches short-term extremes early. When both of them stretch to the same side at once, the message is far more convincing than either alone.