So i built a quad frame which measures 230mmx230mm(length x width). and 330mm approximately diagonally.then it hit me what is the maximum propeller size that can be used on this frame.so i am just asking anyone who can enlighten me on this.
note -the max prop size need not be necessarily the one which is optimum  for the quad.
thanks in advance

Theoretically=8inch prop
practically i think it can have 7inch pretty easily

Thanks. One question though. 230mm= approx 9".why is the prop size limited to 8"?i am not saying that i will go for 9045 props but just curious as why 8" max?

Ignoring all else, the max prop size on that frame would be slightly less than half the distance from centre to centre of mounting holes at each corners. Slightly less than half is to ensure clearance between the two adjacent props, the diagonal distance is immaterial here since it is square frame 
Generally you do not get 8 1/4, 1/2, 3/4 props hence practically 8 is what was recommended   

sorry it's already answered

So i can easily go for 8" props?  Since slightly less than 9" is 8" wat i can get. Is this right?