Search icon

Social Media

12th Oct 2023

Optical illusion shows hidden number – and everyone is seeing it differently

Kieran Galpin


It’s the white and gold dress all over again

People on social media are losing their marbles trying to wrap their head around an optical illusion that seemingly appears differently to different people.

We all remember that insufferable white and gold dress – or was it blue and black? Either way, the illusion had people gripped for months and now, it might be happening all over again.

The illusion was initially posted by Twitter user @benonwine, before being shared across just about every social media platform there is. Some people are seeing 45,283 at first, then 34,528,39 upon closer inspection.

Reacting to the puzzle on Twitter, one user wrote: “45 283…and what’s the catch? Should I book an appointment with my GP?”

Another said: “I can only see 528. Does that mean anything about my eyesight?”

One theory points to contrast sensitivity as the culprit. Essentially, contrast sensitivity dictates the amount of contrast needed to detect an object such as the numbers hidden in the now-viral image.

“Contrast sensitivity is the ability to distinguish between an object and the background behind it,” The Vision Centre explains on its website. “High spatial frequencies make up detailed features such as sharp edges, facial features, and similar. Low spatial frequencies are more like coarse images, where you can see the overall shape of something but not detailed features.”

They continued: “A contrast sensitivity test measures how well you can tell the difference between light and dark. For this, your doctor will use a different type of chart where the characters fade from black to grey gradually.

“Visual acuity is measured when you read the eye chart during an exam. This is considered a high contrast test (black letters on a white background).

“You can have excellent visual acuity, but reduced contrast sensitivity and vice versa.”

Related links: