I'm not entirely sure about the number of paid subscribers on Unacademy, but from what I've seen, there are quite a few. The majority of the courses on Unacademy are free, but there are a number of premium courses that cost money to access. In order to become a paid subscriber, you have to sign up for a monthly or yearly subscription plan. With a paid subscription, you get unlimited access to all of the courses on Unacademy.