How Many Triangles Can You Find in This Figure?
If you've seen a picture puzzle shared on Facebook with the caption 'only a genius can solve this,' it's probably the how-many-triangles puzzle. It's been around for decades and still goes viral every few months because the answer is consistently higher than people expect.
Count every triangle in the figure below, including the ones formed by overlapping lines. Small triangles count. Medium triangles count. The big outer triangle counts too.
Why this puzzle fools your brain
When you look at a figure made of overlapping triangles, your brain isolates the smallest closed shapes and counts those. It doesn't naturally treat a group of small triangles as one larger triangle, even though geometrically it is. The brain prefers atomic units — it's harder work to mentally 'glue' shapes together into a bigger version of themselves.
There's also a working-memory limit. By the time you've counted the small triangles, you've forgotten where you started, so when you try to count medium triangles you double-count or skip some. That's why people get inconsistent totals every time they try.
How to actually solve it
Count by tier. Tier 1: the smallest triangles only. Tier 2: triangles made of two small ones joined together. Tier 3: triangles made of four small ones. Tier 4: the largest outer triangle. Write each tier's count down before moving to the next so you don't lose track. Add them at the end.
Try another picture puzzle
- How Many Squares?The classic 'how many squares' picture puzzle. Most people stop at 16 and miss the rest. Try it, get a hint, then reveal the real answer.
- The Impossible TriangleThe Penrose triangle looks solid, but it can't exist in 3D. Trace each beam with your finger and you'll see why. Famous impossible-object illusion.
- Find the Hidden CatA tabby cat is hiding in a cozy living room scene. Most people take 30 seconds to spot it. Can you find it in under 10?