What is a Symmetrical Triangle? Definition, Formula, and Example
A symmetrical triangle is a continuation chart pattern in which price compresses between a descending resistance line of lower highs and an ascending support line of higher lows, with both trendlines converging toward an apex at roughly mirror-image angles.
Symmetrical Triangle Definition
A symmetrical triangle is a continuation chart pattern formed when price oscillates between a descending resistance line connecting lower highs and an ascending support line connecting higher lows, with both trendlines converging toward an apex at roughly the same angle. Neither side dominates — the pattern reflects equilibrium between buyers and sellers and resolves in the direction of the prior trend roughly 60% of the time. Unlike ascending or descending triangles, the symmetrical version has no directional bias built into its shape.
How to Identify a Symmetrical Triangle
Five criteria define a textbook symmetrical triangle:
1. At least two lower highs touching a downward-sloping trendline
2. At least two higher lows touching an upward-sloping trendline
3. Trendline slopes mirror each other within ~10° of symmetry
4. Volume contracts as the apex approaches
5. Breakout occurs at 50–75% of the way to the apex; later breakouts fail more often than they succeed
Measured-move target: project the height of the widest part of the triangle from the breakout point. A $70-tall triangle that breaks at $895 projects to $965 on the upside.
Worked Example
NVDA consolidated through April 2026 between $850 and $920, forming lower highs at $920, $905, and $895 against higher lows at $852, $865, and $878. The widest section of the triangle measured $70. NVDA broke above $895 resistance on May 4 with volume 1.6× its 20-day average. The measured move projected $965; the stock traded to $968 by May 19, a 7.5% gain in 11 sessions.
When Traders Use It
The symmetrical triangle is most useful as a continuation setup after a strong directional leg. Momentum traders use it to time entries on names that have already run, where chasing the prior breakout is too late but waiting for a full reversal sacrifices the trend. Volume confirmation is non-negotiable — a breakout on declining volume reverses far more often than one on expanding volume. Position sizing is straightforward: stop below the opposite trendline, target the measured move, and the risk:reward usually clears 2:1.
Limitations and Common Misconceptions
- The 60/40 directional split means symmetrical triangles are not strongly predictive on their own — context (prior trend, market regime, sector flow) carries the bias
- The pattern is often unclear in real time; trendlines get redrawn as new pivots print
- Apex breakouts — those occurring in the final 10% of the pattern — fail at a high rate because the energy has dissipated
- A "breakout" without a volume spike is usually a fakeout
- Symmetrical triangles on low-volume tickers are statistical noise, not patterns