Recently, a friend asked me how to use the RSI indicator. I found that many people are actually both familiar with and unfamiliar with this tool. RSI stands for Relative Strength Index, which essentially uses values between 0 and 100 to measure the comparison of upward and downward momentum over a period of time. The closer the value is to 100, the stronger the upward momentum; the closer to 0, the more dominant the downward trend.

The concept I personally use most often is overbought and oversold. When RSI exceeds 70, the market is often overly optimistic, and a pullback is likely; conversely, when RSI drops below 30, the market may be overly pessimistic, and a reversal could occur. But I want to remind you that overbought and oversold only indicate short-term overreaction, not a guaranteed reversal. False signals are especially common in strong trending markets.

Regarding the best parameters for RSI, I think it depends on your trading style. The default RSI 14 is the most balanced choice, suitable for medium-term trading like 4-hour and daily charts. If you prefer short-term trading, you can try RSI 6, which reacts much faster, but the false signals will also increase. Conversely, RSI 24 is suitable for long-term investors; it can effectively filter out noise and improve accuracy, but trading signals will be less frequent.

Besides overbought and oversold, RSI divergence is also a signal I often use. Divergence occurs when the price makes a new high but RSI doesn’t follow with a new high, or the price makes a new low but RSI doesn’t make a new low. Bearish divergence usually indicates weakening upward momentum and may signal a correction; bullish divergence suggests exhaustion of downward momentum and a potential rebound. However, divergence is not foolproof; I usually confirm it with trendlines or candlestick patterns.

The biggest mistake I’ve made is relying too heavily on a single indicator. Sometimes, on the hourly chart, RSI shows an oversold signal, and I rush to enter the trade, only to realize that on the daily chart, RSI has already broken below the 50 midline, trapping me. So now, my habit is to look at multiple timeframes simultaneously, and I always verify with other indicators like MACD and moving averages.

If you’re a beginner, I recommend starting with RSI 14 and the overbought/oversold zones to get familiar, find parameters that suit your trading cycle, and then gradually incorporate divergence signals. Most importantly, don’t treat RSI as a万能工具; it’s just an auxiliary tool to help you judge whether the market is overreacting or if the momentum is still strong. True trading success still depends on a comprehensive trading system and risk management.