Triangle Patterns: Ascending, Descending and Symmetrical Triangles

Where this page's information comes from

• StockCharts' ChartSchool, its guides to the ascending, descending and symmetrical triangle, for the conventions on anatomy, volume, retests and targets. Those points are attributed in the text.
• Thomas Bulkowski's triangle pages and glossary on ThePatternSite, for his qualitative points on prior trend, confirmation and targets, and his definitions of pullbacks, throwbacks and busted patterns.
• TradingLoot's own explanations and diagrams. They describe how triangles are commonly read, not rules that guarantee an outcome.

Bulkowski's pages also publish performance statistics. This guide leaves them out, because the market, period and method behind them aren't set out on those pages. For how he measured patterns, see our summary of his encyclopedia.

How a triangle forms

Each triangle needs two boundaries, and each boundary needs at least two touches: ChartSchool asks for two or more highs to draw the upper line and two or more lows to draw the lower one. As the lines converge, the range narrows and price has less room to move before it leaves the pattern.

The sources differ on the trend that comes first. ChartSchool says an established trend should exist for a triangle to qualify as a continuation pattern. Bulkowski's identification notes say the price trend leading into a triangle can be in any direction. In TradingLoot's view, the prior trend is useful context for reading a triangle, but it doesn't decide which way the triangle will break.

Ascending triangle

An ascending triangle has a flat upper boundary, drawn through similar highs, and a rising lower boundary, drawn through higher lows. ChartSchool describes it as usually forming as a continuation pattern in an uptrend, sometimes as a reversal, and reads it as bullish wherever it forms. That reading is its interpretation: the pattern can still break downward through the rising line, which is why the diagram shows that exit as an alternative.

Descending triangle

The descending triangle reverses the picture: a flat lower boundary through similar lows, and a falling upper boundary through lower highs. ChartSchool describes it as generally forming as a continuation pattern in a downtrend, sometimes as a reversal, and reads it as bearish wherever it forms. Again, that is its interpretation. Our summary of Bulkowski's encyclopedia notes that his preferred setup in a 2006 interview was a descending triangle that broke out upward.

Symmetrical triangle

A symmetrical triangle has lower highs and higher lows, so both boundaries slope toward an apex. ChartSchool says it more often marks a continuation of the current trend than a reversal, but it is explicit that the direction of the next move can only be determined after a valid breakout, and it warns that trying to guess the direction in advance can be dangerous.

Timing within the pattern also matters to ChartSchool: it treats a break very early in the pattern as possibly premature, and a break very close to the apex as possibly insignificant, since price has to leave a narrowing range at some point.

Why direction isn't fixed

Names like "ascending" and "descending" describe the shape, not the outcome. ChartSchool labels ascending triangles bullish and descending triangles bearish, while Bulkowski's research measures breakouts in both directions for all three types. Both views are useful, but they lead to the same practical point: until price leaves the pattern convincingly, you don't know which way it will go. As the hub explains, a shape's name doesn't fix the direction of its breakout.

A confirmed breakout tells you the direction price actually took when it left the triangle. It doesn't guarantee that the move will continue, reach a target or hold. Treat it as the start of a new reading, not the end of one.

Confirmation and volume

On his descending triangle page, Bulkowski treats the pattern as confirmed when price closes outside one of its trendlines. ChartSchool notes that some traders add price or time filters before trusting a break; the hub explains that trade-off.

For volume, ChartSchool describes a common tendency: volume usually contracts as a triangle develops, and an expansion on the breakout is preferred as confirmation, though not always necessary. For symmetrical triangles, it stresses expansion especially on upside breakouts.

How much weight volume can carry also depends on the data. In TradingLoot's view, the volume a platform shows may not represent the whole market, for example where trading is spread across many venues, and some feeds show tick counts rather than traded volume. Treat volume as one input to weigh, not a switch that confirms or cancels a triangle.

Retests, pullbacks and throwbacks

ChartSchool notes that a broken boundary often swaps roles: broken resistance in an ascending triangle can act as support, and broken support in a descending triangle can act as resistance. It also says plainly that sometimes price comes back to test the level and sometimes it doesn't.

Bulkowski names the returns by direction: a throwback after an upward breakout, and a pullback after a downward one, each a return to the breakout price within 30 days. A retest is a possibility, not a step in the pattern, and a return that carries back through the boundary is the start of a failure, not a retest.

The measured-move convention

The usual convention measures the widest part of the triangle and projects that distance from the breakout, upward for an upward break and downward for a downward one. ChartSchool describes it this way for all three types, and Bulkowski's pages add or subtract the pattern's height from the breakout price in the same spirit. Marker 5 in the first two diagrams shows the idea.

ChartSchool calls these targets guidelines, to be weighed against other analysis. They are reference points, not forecasts of distance or timing. For why TradingLoot doesn't publish hit rates for targets, see probabilities and limits.

Similar patterns

Some other consolidation shapes have converging or parallel boundaries. These sections compare them with triangles:

• Wedges compared with triangles
• Pennants compared with symmetrical triangles
• Rectangles compared with symmetrical triangles

Shape invalidation and failed breakouts

Two different things can go wrong, and they are worth keeping apart. The first is about identification: before any breakout, price can stop fitting the shape. ChartSchool gives a textbook rule for descending triangles: if a later reaction high equals or exceeds the previous one, the shape no longer qualifies. That is an identification rule from one source, not a universal market rule, and this guide doesn't extend it to the other triangles.

The second is about the breakout. Price can leave the triangle, make little progress, and come back through the boundary it broke. That is a failed breakout, shown below. ChartSchool's symmetrical triangle guide notes that reversal patterns can be especially difficult to analyse and often produce false breakouts.

Bulkowski uses a narrower, technical term for one kind of failure. His busted pattern is one where price moves no more than 10% after the breakout, then reverses and crosses the other side of the pattern, starting a trend in the new direction. Not every failed breakout meets that definition, and the diagram doesn't measure it. For why failures still carry information, see our summary of Bulkowski's research on failure.

Textbook vs live charts

Live triangles are rarely as neat as the diagrams. The flat boundary may be a zone rather than a line, touches may overshoot slightly, and the same swings can often be read as more than one shape. The two lines you draw decide the pattern, so it helps to draw them before a breakout rather than fitting them afterwards.

In TradingLoot's view, practising on historical data with replay is a good way to check whether you would have drawn the same boundaries in real time.

Common misreadings

These are ways triangles are often misread, as TradingLoot sees it.

"An ascending triangle always breaks upward."

Any triangle can break either way. Some sources lean one way; the breakout decides.

"A confirmed breakout means the move will continue."

It shows the direction price took. It doesn't guarantee follow-through.

"If the shape stops fitting, the trade has failed."

Before a breakout, that's a question of identification. A failed breakout is a separate event.

"The measured move tells you where price will go."

It's a convention for a rough reference point, not a forecast of distance or timing.

"Low volume on the breakout cancels the pattern."

Volume is supporting evidence, and what it means depends on the market and the data you're seeing.

Key takeaways

• Triangles differ by which boundary is flat and which slopes, or whether both converge.
• Any triangle can break either way; bullish and bearish labels are a source's interpretation.
• A confirmed breakout shows the exit direction, not how far the move will go.
• Shape invalidation and a failed breakout are different problems.
• Volume and measured moves are supporting evidence and conventions, not certainties.
• A busted pattern is Bulkowski's narrower definition of one kind of failure.

Further reading

• Head and Shoulders Pattern: a reversal pattern confirmed by a break of its neckline.
• Double Top and Double Bottom Patterns: two similar peaks or lows, confirmed by a break of the level between them.
• Encyclopedia of Chart Patterns by Thomas Bulkowski: how he measured patterns, including triangles that break both ways.
• Technical Analysis of the Financial Markets by John J. Murphy: a broad foundation in which price patterns are one of many tools.
• Chart Patterns: the method that applies to every pattern.