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This optical illusion shows a hidden number which everyone is seeing differently

By Alma Fabiani

Feb 25, 2022


Who doesn’t love being presented with an optical illusion confusing enough to drive the internet apart? We all remember the dress that caused chaos online and divided netizens into two sections: the ones who thought it was blue and black, and those who saw it as white and gold. Well, it looks like we might be up for another round as an illusion with a number concealed in it swamps social media platforms.

The image shows a black and white circle with a number hidden within it—the one million dollar question is, what number?

At first glance, many are seeing 45283. But on closer inspection, it appears to be 3452839—at least to some people with very good eyesight. We personally can’t see it. Meanwhile, others only decipher 528 out of the trippy image.

One Twitter user went as far as linking the potential answer to this mind-screwing illusion with the dress.

It seems that the illusion is a measure of contrast sensitivity, another user noted under the now-viral tweet. Contrast sensitivity measures the amount of contrast required to detect an object, such as the numbers in the mysterious image, and it varies between people. You can have excellent visual acuity but reduced contrast sensitivity and vice versa. It can also be a symptom of other eye conditions however, such as cataracts or glaucoma. Night driving, for example, is an activity that requires good contrast sensitivity for safety.

If you’re among those struggling to see more than the number 528, then you might be in need of a contrast sensitivity test, which will measure how well you can tell the difference between light and dark. For this, a doctor will use a different type of chart where the characters fade from black to grey gradually.