RSI = 100 − [100 / (1 + (Average Gain / Average Loss))]
RSI is a 0–100 momentum gauge; under 30 is oversold, over 70 overbought.
What it is
The Relative Strength Index is a technical momentum indicator that measures the speed and size of recent price changes on a 0-to-100 scale. It is typically calculated over 14 periods. Readings above 70 are often called overbought and below 30 oversold, though these are conventions, not rules.
Why it matters
RSI helps traders gauge whether a recent move has been unusually strong in one direction and may be due to pause or reverse. The pitfalls: in a strong trend RSI can stay overbought or oversold for a long time, so it is a context tool rather than a standalone buy or sell signal, and different period settings change the readings.
How it's calculated
Compute the average of up-day gains and down-day losses over the period, take their ratio (relative strength = average gain / average loss), then convert it to a 0–100 scale.
How Quintarthai uses it
Momentum and technical metrics such as RSI are available across the screener and company pages; view a stock on its deep-analysis page.
FAQ
Does an RSI above 70 mean I should sell?
No — overbought just means momentum has been strong; in a powerful uptrend RSI can stay above 70 for a long time without reversing.
What period is RSI usually calculated over?
The standard setting is 14 periods (often 14 days), but traders adjust it; shorter periods make RSI more sensitive and noisier.
Check your understanding
A stock's RSI has been above 70 for several weeks during a powerful uptrend. What is the most reasonable takeaway?
RSI is a momentum oscillator, and in a strong uptrend it can remain above 70 for a long time, so an overbought reading is contextual rather than an automatic sell trigger or a valuation measure.