读懂RSI

The **Relative Strength Index (RSI)** is a momentum oscillator that measures the speed and change of price movements on a scale from **0 to 100**. It was developed by J. Welles Wilder and is one of the most widely used technical indicators.

### Standard RSI Interpretation (14-period is the default and most common)

RSI Level	Traditional Meaning	Typical Market Condition	Common Trading Interpretation
70–100	Overbought	Price has risen too far, too fast	Potential pullback or reversal downward
30–70	Neutral / Healthy range	Normal trending or ranging market	No extreme condition; trend can continue
0–30	Oversold	Price has fallen too far, too fast	Potential bounce or reversal upward

### What is considered a “healthy” RSI?
- **40–60** is generally seen as the healthiest, most sustainable range for a strong trend.
  - In a **strong uptrend**, RSI often stays between **40–70** (rarely drops below 40).
  - In a **strong downtrend**, RSI often stays between **30–60** (rarely goes above 60).
- Staying in the 40–60 band for long periods indicates a healthy, controlled trend without excessive momentum that could lead to reversal.

### Classic Overbought / Oversold Levels

Condition	RSI Level	Notes
Overbought	≥ 70	Very common threshold. Some traders use 80 for stronger confirmation in bull markets.
Oversold	≤ 30	Very common threshold. Some traders use 20 for stronger confirmation in bear markets.

### Important Variations & Adjustments Traders Use

Market Environment	Adjusted Overbought	Adjusted Oversold	Reason
Strong bull markets	80–90	30–40	RSI stays elevated longer
Strong bear markets	50–60	10–20	RSI stays depressed longer
Range-bound markets	70 / 30 (standard)		Classic levels work best
Very short timeframes (e.g., 2–7 period RSI)	80–90 / 10–20	Tighter extremes because shorter RSI is more sensitive

### Summary Table (Most Common Settings)

RSI Value	Interpretation	Action Most Traders Consider
Above 70 (or 80)	Overbought	Caution; possible short/sell signal or take profit
50–70	Bullish / Healthy uptrend	Trend is strong but not extreme
40–60	Ideal healthy trend zone	Best area for trend continuation
30–50	Bearish / Healthy downtrend	Trend is strong but not extreme
Below 30 (or 20)	Oversold	Caution; possible long/buy signal or bottom

Bottom line:
- Healthy RSI for a sustainable trend → **roughly 40–60**
- Classic oversold → **≤ 30**
- Classic overbought → **≥ 70**

These levels are guidelines, not hard rules—always use them with price action, trend context, and other indicators.