Optical illusion: Only the brightest brains can count all the 3s in this visual puzzle

Optical illusions are not only cool to look at—they're also master tools that challenge how sharp the human brain is. Such brain puzzles fool your eyes and brain, testing your perception, eye for detail, and pattern spotting. From concealed numbers to concealed shapes, they put your brain into overdrive. One of these viral challenges is taking the internet by storm: a puzzle filled with the digit "3" that's stumping even math geniuses. Think you can solve it? Take another look, you might be surprised at what you don't notice.

The puzzle

A brain teaser shared on X (previously Twitter) by account Emmygold has piqued interest with its easy-but-cunning premise. The challenge is to count every 3 in a series—"31343353533"—shown across the top of a picture. What makes it more challenging is the inclusion of a standard phone keypad grid at the bottom of the series, quietly contributing to the difficulty. Although it appears to be a simple task, the visual presentation can easily trick the eyes into missing hidden 3s and doubting one's ability to observe.

Observation tips to notice:

• Slowly scan the image, don't let your eyes fly by concealed details.
• Zoom in to spot faint or subtly placed number 3s.
• Divide the image into sections and count section by section.
• Look out for upside-down, mirrored, or camouflaged representations of the number 3.

Let's make it more challenging!
Set a timer for only 15 seconds and scan through to locate the 3's that are hidden in this puzzle.

How many 3s did you finally spot?