Triangle Patterns: Symmetrical, Ascending and Descending

What is a triangle pattern?

A triangle is a shape in which the range of price swings narrows steadily and the line joining the highs and the line joining the lows converge on a single point. Drawing a line takes two points, so a shape is usually called a triangle only when there are at least four turning points, that is, two highs and two lows. The point where the two lines meet is called the apex, and the widest part, where the triangle begins, is called the base. Triangles are divided into three types by the slopes of the two lines. In terms of participant behaviour, falling highs are read as sellers stepping in earlier and earlier, and rising lows as buyers stepping in earlier and earlier. Each side waits for the other to give way first, and the range narrows. When drawing the lines, first make sure there are at least four turning points and decide whether to fit the lines to wicks or bodies, then check that the lines do not cut carelessly through candles. Many people regard a line touched three or more times as more reliable.

• Symmetrical triangle: highs get lower and lows get higher
• Ascending triangle: highs stay flat while lows get higher
• Descending triangle: lows stay flat while highs get lower
• If both lines slope the same way while narrowing, it is a wedge

A symmetrical triangle does not tell you the direction

A symmetrical triangle is a shape in which each high is lower than the last and each low is higher than the last. It is explained as buyers and sellers both backing off a little at a time, so the price range shrinks. Textbooks often classify it as a continuation pattern that resolves in the direction of the prior trend, but the shape itself carries no information about direction. As in the chart below, a symmetrical triangle after an advance can also break down. The direction is confirmed only after a close outside one of the two lines. A small symmetrical triangle that forms briefly right after a sharp move is called a pennant, and it is covered in the article on flag and pennant patterns. A common mistake is to decide in advance that it will resolve upward because the prior trend was up. Seen that way, even a candle breaking the lower line gets dismissed as a brief wobble. The order of checks is which line a closed candle finished outside of, how that candle's volume compares with the recent average, and whether price stays out rather than returning inside the triangle. The starting point is to accept a break against the prior move, as in the chart, as just as much an outcome.

Ascending and descending triangles

An ascending triangle is a shape in which the highs keep getting blocked at the same price while the lows rise steadily. It is read as meaning there are persistent sell orders at that price, but buyers keep stepping in at a higher price each time. A descending triangle is the reverse: price keeps finding support at the same level, but the highs keep coming down. Textbooks describe ascending triangles as tending to resolve upward and descending triangles downward, but they sometimes resolve the other way, so this too is only a possibility until confirmation. As in the article on drawing support and resistance, it is more natural to treat the flat side as a zone with some width rather than a single price, and the Support & Resistance Finder groups clusters of swings into zones for the same reason. For an ascending triangle, the explanation is that price moves quickly once the sell orders stacked at the flat line are absorbed, but how many of those orders remain cannot be seen on the chart. The yardstick is not how many times price touched the flat line but whether a candle closed beyond it.

Volume and volatility shrink as it converges

Inside a triangle, volume is described as tending to shrink along with the price range as it narrows. The lower panel of the first chart mimics that. Because the candles move less, Bollinger Band width and ATR also move lower. If you use the Bollinger Band Squeeze Scanner to find coins whose bandwidth has narrowed, you will sometimes see a triangle-like shape on the chart as well. But lower volatility only means a large move may come; it does not say which way. Many explanations cite rising volume on the breakout as confirming evidence. When reading a drop in volatility, measure it against the same instrument's own history. A narrow bandwidth on something that normally moves little is just its usual state, whereas the narrowest bandwidth in several months on something that usually moves a lot is a change worth noting. The first move out of a squeeze can also reverse straight away, so look at the direction in which volatility starts expanding again together with that candle's close.

Measured target: the widest part, projected from the breakout

The most widely used measured target for a triangle takes the base, the widest vertical distance at the start of the triangle, and moves that amount from the breakout (or breakdown) point. In the descending triangle below, the height of 18 between the first high of 118 and the flat support of 100 is subtracted from 100, where support broke, giving 82. The height varies slightly depending on where you measure the base (at the first high, or where the two lines begin), so the target also differs from person to person. As in the head and shoulders and double bottom articles, this value is a reference that transfers the pattern's size; it does not mean price will reach it. In real judgment you also look at what lies on the way to the target. For a descending triangle, check whether an earlier low or a level where price lingered sits above the measured target; for an ascending triangle, whether an earlier high sits below it. If such a zone exists, it is described as common for price to stop before reaching the target. Writing down which base you used for the target lets you review it later on the same basis.

The convention that meaning fades near the apex

The classic explanation treats a breakout somewhere between half and three quarters of the way from the base to the apex as typical. If no breakout comes until price almost reaches the apex, the gap between the two lines gets so narrow that the slightest move carries price outside a line, and such an exit is seen less as the pattern's outcome than as price simply drifting out. So the convention is to treat a triangle that has run close to its apex as having lost its meaning and to read the chart afresh. This too is a convention born of experience, not a verified rule. In the narrow end, even small wobbles easily push a wick past a line before it returns inside; how to confirm with closes, retests and volume, and the cost of being late while you wait for confirmation, are covered in the article on breakouts and false breakouts. In practice, when a triangle has run close to its apex, many people redraw the lines or look at the same stretch on a larger timeframe. What was near the apex on a small timeframe may still be a wide section on a larger one.

Limits: everyone draws a different triangle

With triangles, the moment you choose which highs and lows to connect and whether to fit the lines to wicks or bodies, the shape and the breakout candle are decided, so different people get different triangles from the same chart. On past charts you draw the lines already knowing the breakout direction, so the pattern looks more reliable than it really is. The statistics this course measured directly do not include chart patterns, and outside success rates that cannot be verified here are not repeated. Reading a triangle as a shape that shows a stretch of shrinking volatility and its boundaries, and confirming direction by a close outside those boundaries, is about as much as can be said about this pattern with relative confidence. One way to reduce this limitation is to fix the drawing rules first. If you decide whether to fit wicks or bodies and how many candles define a turning point, and draw with the same rules every time, you at least cut down on moving the lines to fit the result you want. This article only explains how to read the shape; it does not tell you what to do when you see the pattern.

What looks different in coins and stocks

If you draw a triangle on intraday stock candles, the lines break off where the regular session ends, and it is common for the next day's open to gap outside the triangle. In that case there is no candle that actually crossed the line, so you first have to decide where to measure the breakout point and the target. Korean stocks tend to trade less around lunchtime and more near the open and the close, so reading that intraday drop in volume as evidence of convergence is an easy mistake. It is also common for the range of US indices, large tech stocks, or names like Samsung Electronics and SK Hynix to narrow ahead of scheduled events such as earnings or rate decisions; such convergence is driven by the calendar more than by the shape. Coins trade around the clock, so the lines never break off, but the range often narrows at weekends or during thin hours, and with their higher volatility, wicks frequently cross both lines in the narrow end. In Korean stocks with a daily price limit (plus or minus 30%), a large break may not happen in one day and can be spread over several, while coins and US stocks have no per-stock daily limit.

A practical checklist

On a live chart the triangle itself keeps changing. Every new high or low changes the slope of a line, and it is common for the candle in progress to poke outside a line and then close back inside. Highs and lows are confirmed as turning points only after a few more candles form to their right, so the last line at the right edge can be redrawn at any time. If a tool that marks triangles or breakouts automatically calculates on the live candle, its signals can appear and disappear with each update, so check again on closed candles.

• Are there at least two highs and two lows as turning points?
• Did you decide whether to fit wicks or bodies, and draw by that rule?
• Is it symmetrical, ascending or descending, and not a wedge with both lines sloping the same way?
• How far along is it from the base to the apex?
• Did a closed candle finish outside a line? (The live candle does not count)
• Did you compare the breakout candle's volume with the recent average on the same timeframe?
• Did you check earlier high and low zones between price and the measured target?

Common mistakes

The most common mistake with triangles is moving the lines to fit the result. When a wick crosses a line, the line gets redrawn slightly further out to keep the triangle alive; when price crosses in the direction you wanted, it is immediately called a breakout. Many people also look only at the converging shape without checking the length of the prior trend or the larger-timeframe move, or mistake a narrow drift during thin trading hours for a triangle. Recording the lines and rules you first drew, and using a close outside those lines as the yardstick, reduces this kind of drift.