RSI Indicator: Complete Guide

The Relative Strength Index (RSI) is one of the most popular momentum indicators in trading. Created by J. Welles Wilder, it measures the speed and magnitude of price changes.


What is RSI?

RSI is an oscillating indicator that ranges from 0 to 100. It measures momentum by comparing the magnitude of recent gains to recent losses.

RSI Scale:
100 ─────────
              ← Overbought (70-100)
     ████
              ← Neutral (30-70)
    ╱    ╲
           ╲
           ████
              ← Oversold (0-30)
0 ─────────

RSI Formula

RSI = 100 - (100 ÷ (1 + RS))

RS = Average Gain ÷ Average Loss

Default settings: 14 periods

Key Levels

LevelMeaning
70+Overbought (potential reversal)
30-Oversold (potential reversal)
50Neutral

RSI Settings

TimeframePeriodSensitivity
Daily14Standard
4-Hour14Standard
1-Hour9-10More sensitive
15-Minute7-9Very sensitive

How to Use RSI

1. Overbought/Oversold (Basic)

Traditional interpretation:

  • RSI > 70 = Overbought = Consider SELLING
  • RSI < 30 = Oversold = Consider BUYING

Problem in strong trends: RSI can stay overbought/oversold for extended periods.

Solution: Only trade reversals in ranging markets.


2. Divergence (Advanced)

Bullish Divergence:

Price:      Lower low
RSI:        Higher low
Meaning:    Reversal potential UP

Bearish Divergence:

Price:      Higher high  
RSI:        Lower high
Meaning:    Reversal potential DOWN

3. RSI MA Cross

RSI crossing its own moving average:

  • RSI crosses above MA = BUY signal
  • RSI crosses below MA = SELL signal

4. Trend Confirmation

TrendRSI Behavior
UptrendStays above 40-50
DowntrendStays below 40-50

RSI below 40 in uptrend = Potential buying opportunity RSI above 60 in downtrend = Potential selling opportunity


RSI Trading Strategies

Strategy 1: RSI Reversal (Range)

Entry Conditions:
- RSI < 30 (oversold)
- Price bounces off support
- Confirmation candle forms

Stop: Below recent swing low
Target: Previous high, or 2:1

Strategy 2: RSI Divergence

Entry Conditions:
- Divergence forms (price vs RSI)
- Price breaks trendline
- RSI crosses back to neutral

Stop: Beyond divergence point
Target: Next structure

Strategy 3: RSI Trend Confirmation

Entry Conditions:
- Uptrend confirmed
- Price at key support
- RSI bouncing from 40-50

Stop: Below support
Target: New high

RSI Best Practices

Timeframes

TimeframeBest For
DailySwing trading
4-HourMultiple-day trades
1-HourIntraday

Markets

MarketRSI Effectiveness
Ranging marketsHigh
Strong trendsLow (stays extreme)
CryptoHigh
ForexMedium

Common RSI Mistakes

1. Trading RSI Alone

Problem: Entering when RSI = 30 without price confirmation.

Result: Price keeps falling.

Solution: Wait for price confirmation.


2. Ignoring Trend

Problem: Buying at RSI = 30 in strong downtrend.

Result: Fighting the trend.

Solution: Use with trend direction.


3. Wrong Period

Problem: Using 14-period on 5-minute chart.

Result: Too many false signals.

Solution: Adjust period to timeframe.


4. No Confirmation

Problem: Trading RSI reading alone.

Result: Low success rate.

Solution: Combine with support/resistance.


RSI vs Other Indicators

IndicatorBest For
RSIMean reversion
MACDTrend momentum
StochasticFast crossovers

RSI Checklist

☐ Trend identified?
☐ RSI at extreme?
☐ Price at support/resistance?
☐ Confirmation formed?
☐ Stop placed properly?
☐ Target set?


RSI shows momentum. Confirm with price.