What you will learn
- Read the RSI scale and understand what levels 70 and 30 stand for
- Tell apart the cases where overbought means reversal from those where it means strength
- Spot divergence between price and the indicator
- Choose an RSI period that fits your timeframe
RSI — the market's overheating gauge
RSI measures momentum strength on a scale from 0 to 100. It answers the question: has the market gone too far, or is there still room?
Above 70 — overbought (buyers are exhausted), below 30 — oversold (sellers are worn out).
Analogy. A market thermometer: above 70 is a fever, below 30 is hypothermia. But a "fever" alone doesn't reverse price — it all depends on whether you're in a trend or a range (see below).
Where RSI actually works
The key thing about RSI: reversal signals are reliable only in a range (accumulation). There the market moves within a band: overbought → pullback, oversold → bounce.
In a strong trend it's different: RSI gets stuck in a zone for a long time — above 70 in an uptrend or below 30 in a downtrend — and the "reversal" never comes, price keeps going.
Beginner's mistake. Selling just because "RSI is above 70" in an uptrend. It can sit in overbought for weeks. Use RSI reversals in a range, and in a trend — trade with the trend.
Break down the RSI zones
The dashed lines are the 70 and 30 levels. Tap all three points and open them to complete the step.
- Overbought
- RSI above 70 — in a range, expect a pullback
- Oversold
- RSI below 30 — in a range, expect a bounce
- Divergence
- Price rises while RSI weakens — a warning sign
This is an exercise from the lesson. You can run it on a live chart in the terminal, where progress is recorded.
Try it on the chartIn a range, extremes pull back
This is a range. On the left RSI spikes above 70 — and right after, the line drops. On the right it dips below 30 — and turns back up. In a band, extremes don't last long.
Remember: this is how it works in a range. In a strong trend RSI could stay in the zone for a long time.
RSI above 70 in a strong trend
The market is in a strong uptrend, RSI is holding above 70. What's the smarter move?
This is an exercise from the lesson. You can run it on a live chart in the terminal, where progress is recorded.
Try it on the chartTap the overbought zone
Overbought is the upper part of the chart, above the 70 level. Tap it.
Check off what you've learned
- I understand the RSI 0–100 scale and the 70 / 30 levels
- Key point: RSI reversals are reliable in a range, not in a trend
- I don't sell just because it's "overbought" in a trend
- I notice divergence between price and RSI
This is an exercise from the lesson. You can run it on a live chart in the terminal, where progress is recorded.
Try it on the chartWhen RSI works and when its signals are useless
This is the central division of the whole lesson. In a range, when the market moves between two boundaries and neither side wins, RSI works almost literally: a push above 70 means buyers are exhausted and price will probably return toward the middle, and a drop below 30 is the mirror image. In that kind of market the indicator genuinely leads price.
In a sustained trend it all breaks down. RSI can stay above 70 for weeks, and every day of that period will look like a sell signal that costs money. The reason is simple: in a trend each new leg is stronger than the pullback before it, and an indicator that measures strength honestly reports that strength is high. That is not a malfunction — it is a correct answer to the wrong question.
The practical conclusion: before you look at RSI, decide whether you are in a trend or a range. In a range, trade the boundaries with it. In a trend, use it differently — not for reversals but for entries with the trend on pullbacks. In an uptrend the 40–50 zone is often where the move resumes, and it is far more useful than waiting for a reversal from 70.
Settings: period, timeframe, levels
The standard period of 14 was chosen by Welles Wilder for daily commodity futures charts, and it remains a sensible default — not because it is optimal but because everyone sees it, which makes it partly self-fulfilling. Changing it should be a deliberate act: a short period (7–9) gives more signals and more noise and suits scalping; a long one (21–25) smooths the picture and leaves only pronounced extremes.
The 70 and 30 levels are not dogma either. On a strongly trending instrument they are often shifted: 40–80 in an uptrend, 20–60 in a downtrend. That is the same move as changing the period — fitting the scale to the character of a particular market rather than applying a universal constant.
On lower timeframes RSI is noisier, simply because price itself is noisier there. If the signals look chaotic, moving up a timeframe usually helps more than tuning the period.
Divergence: what it is and why it is not a signal on its own
Divergence is a disagreement between the direction of price and of the indicator: price prints a new high while RSI at that high is lower than at the previous one. It reads as: the move continues, but with less force than before. A warning sign, yes; an instruction to open a trade, no.
The most expensive mistake is entering on divergence alone. A strong trend produces three or four in a row, and the first two take your stop. Divergence becomes workable when it coincides with something else — a range boundary, a level price has already turned from, a break in structure. It is a good reason to pay attention and a poor reason to press the button.
Three mistakes almost everyone makes
First: selling merely because RSI is above 70. This is the most costly habit in working with the indicator — in a trend it means standing against the move again and again.
Second: treating RSI as a standalone system. It measures the strength of a move and nothing else: it does not show levels, does not give you a stop, and knows nothing about the news. Combined with levels and volume it is useful; on its own it is a set of oscillations.
Third: tuning the period until the indicator shows a pretty history. On past data a flattering period can always be found; it carries no predictive power.
Frequently asked questions
- What does RSI above 70 mean?
- That upward movement has been strong relative to pullbacks over the last N candles. In a range that usually precedes a move back down. In a sustained trend it simply confirms strength, and the reversal may not arrive for weeks.
- What RSI period should I use?
- 14 by default. For scalping on lower timeframes, 7–9, though you will get noticeably more signals and some of them will be noise. For a smoother picture, 21–25. There is no universally best value.
- Why doesn't RSI work?
- Most often because it is being used in a trend as a reversal indicator. That is not a fault of the indicator but the wrong context: overbought and oversold signals are designed for a ranging market.
- How is RSI different from the stochastic?
- RSI compares the strength of gains with the strength of losses over a period. The stochastic shows where the close sits within the recent range. The stochastic reacts faster and produces more false signals; RSI is calmer.
Other lessons in this track
- VolumeHow to read trading volume and use it to confirm price moves.
- EMAMoving averages 20/50/100/200 as trend support and resistance.
- MACDMomentum and trend change from the histogram and lines.
- Structural MarkupRemove the noise and see the key peaks and troughs.
- FractalsLocal extremes by Bill Williams.
- Trading sessionsAsia · London · New York and their character.
- WeekendWhy weekends are dangerous: thin liquidity and gaps.
Terms covered
This material is educational and is not individual investment advice.