People are struggling to find the 16 circles in this bizarre illusion — and only a few can see them

Optical illusions can really have one questioning their intelligence. While some enjoy the mental workout as a means of sharpening their cognitive skills, others regret wasting hours when the answer was obvious. Take this mind-bending puzzle, for instance. There are 16 circles hidden within the image. Can you spot them all? If you can, you're among the rare few. Many can’t, and that’s precisely why it was dubbed the 'Best Illusion of the Year' in 2006.

The image bears an arrangement of grey, white, and black lines forming several rectangles. But within it also exists circles in plain view. As reported by Upworthy, netizens found the puzzle extremely tricky as they sat counting and re-counting the circles, as their mind played tricks. On X (formerly Twitter), a person (@SMcfarnell) commented, “For me, I wouldn’t say the image appears changed forever. I can see the circles, but then the squares strongly reassert themselves. Wow, now I am implying shapes have agency.” Another (@NeuroPoetica) noted, “I absolutely could not see these circles until I played with the levels. Here are three spotlights with adjusted levels. They are across all four lines evenly spaced between the boxes, kind of overlapping with the sides of the boxes.”

Similarly, one (@f0reverf0rn0w) chimed, “I can see them, but when I focus my eyes, it goes back to rectangles. If I relax them on the center point between the rectangles, magic eye style, the circles are visible again.” A frustrated scroller (@Saxgod) echoed, “Starting to wonder do I need bad vision to see the circles? When I take my glasses off, I can kinda see what people are saying, or squint my eyes to mess my vision up. If that is how to see circles, NO THANKS.”

At first, all you see are vertical lines—no curves, no circles, just rectangles. The trick is to shift your focus to the vertical lines between the rectangles—the circles magically appear. If you are still stuck, don’t worry! A good Samaritan in the comment section outlined one of the hidden circles with color to make it easier to spot. And once you see them, switching between rectangles and circles becomes effortless. Finding the first one is the real challenge.

The illusion, known as the Coffer Illusion, was designed by Stanford University psychologist Anthony Norcia, as reported by Only Good News Daily. He explained, "For most people, the grouping into rectangles initially dominates. This may be because rectangles are often more common than circles in our daily environment, and so the brain favors the grouping that delivers rectangular shapes." So it seems, it's safe to say, optical illusions really do challenge the way we think and see beyond the obvious.