Ok Cupid is completely free, meaning you don't have to pay to see more matches or to unlock specific features that may make it easier for you to find someone interesting.
At the same time, because it's completely free, the array of potential matches you get can be wild and varied, to say the least.
There are entire blogs around the web dedicated to the types of people you'll find on Ok Cupid, and part of it is because the service is rapidly growing, free, and accessible to everyone.
Granted, that also means that if you're looking for the most possible matches, and the service is very proud of its matching algorithm.
You have plenty of places to try and find your perfect someone.