A letter-filled optical illusion is perplexing the minds of internet surfers everywhere.

The brain teaser is from Jargainjosh.com and shows nine rows and 31 column’s of the letter X mixed in with a few other hidden letters.

[Warning: Spoilers below]

“You need to think a little differently for coming on to the solution as the answer won’t be right in front of you. So, we have come up with an interesting brain teaser where you have to spot 6 hidden Ys among the group,” according to the website.

“An alert mind can identify 6 Ys within 13 seconds … This brain teaser is just another fun way to test your IQ.”

Can you make out each of the hidden Y’s in 13 seconds or less? Start the timer!

Each row, except for for three, did not have a Y and most of the Y’s were located within the same corridors of the illustration.

“Some puzzles don’t necessarily require mathematics skills or lateral thinking but are a simple test of your observation skills,” the site reads.

“This riddle was tricky but simple as it needs less time and brain power to solve. But it sure feels great when you figure out the answer in a few seconds.”