How many black dots do you see?

Optical illusions are always interesting and fun. Can you see the image below and identify how many black dots there are?

It's not as easy as it seems! And, if you want to understand why, read the article here.
Meanwhile, don't get too worked up about your eyesight, and share this fun with others!

(Source: http://www.theverge.com/2016/9/12/12885574/optical-illusion-12-black-dots)