Social media users are struggling to spot the numbers that are hidden into a swirling image.
The image, posted to Twitter by @benonwine, showed a black and white striped circle with numbers hidden inside of it.
However, the line space and direction vary, making it impossible to decipher exactly what the numbers are.
“Do you see a number? If so, what number,” the optical illusion was captioned.
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Shop NowBut, that didn’t stop X, formerly known as Twitter, users from attempting to figure out the numbers.
“45,283 … and what’s the catch? Should I book an appointment with my GP,” one social media user guessed.
One said they could only spot a few numbers, but they did have an intense glasses prescription to help them see.
Another said: “I can see 45,283, since looking at the other replies … others are seeing two other numbers. I can see there are numbers there but can’t make them out.”
“3,452,839, but to be honest the first 3 is a bit of a guess. Can’t get a fix on it. Easier to see if you jiggle the image up and down, but I don’t know why,” another pointed out.
One said: “Initially 15,283 then I expanded the image and it became 3,452,839!”
The entire number in the image, which works using contrast sensitivity, is 3,452,839.
Contrast sensitivity is the ability to perceive clear outlines of small objects, or identifying tiny differences in shadings and patterns.
There are real-life scenarios where a lack of contrast sensitivity could post an issue.
For instance, things that indicate a lack of contrast sensitivity being unable to read when the paper and text are of similar colour, tripping over curbs or steps and driving in certain conditions.
People with reduced visual contrast sensitivity are advised to avoid driving during low light, fog, glare or rain.