RSI (Relative Strength Index)
Also called: relative strength index
A momentum oscillator from 0–100 that measures the speed of recent gains vs losses — above 70 is often 'overbought', below 30 'oversold'.
Developed by J. Welles Wilder, RSI compares the average size of up moves to down moves over a lookback (commonly 14 days). High readings mean price has risen quickly; low readings mean it has fallen quickly.
RSI is best used for context, not as a standalone signal: 'overbought' can stay overbought in a strong trend. Divergence — price making a new high while RSI doesn't — is a popular warning of fading momentum.
On StockSetups
RSI is one of 30+ indicators on every StockSetups signal; you can screen and sort the board by it, and the dossier also flags RSI/MACD momentum divergence automatically.
Frequently asked
What is a good RSI level to buy?
There's no universal level — many traders watch for RSI turning up from oversold (below 30) in an uptrend, but RSI is context, not a buy button. It works best combined with trend and structure.
Related terms
See rsi (relative strength index) on tonight's board.
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