Relative strength index
Also called: RSI, overbought, oversold
A momentum oscillator from 0 to 100 that compares the size of recent gains with recent losses, usually over 14 periods.
RSI = 100 − 100 ÷ (1 + average gain ÷ average loss). Readings above 70 are called overbought and below 30 oversold, but these describe strong recent moves, not coming reversals; in strong trends RSI can stay extreme for weeks.
Learn more in these lessons
- The relative strength index (RSI)How is RSI calculated, and does an RSI above 70 mean a fall is coming?
- The stochastic oscillatorHow does the stochastic oscillator work, and when does it mislead?
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