GPA conversion

I have an academic score of 64%.. and all the universities ask for the academic score in terms of GPA..
Actually what's the process to calculate percentage in terms of GPA ?
What is the minimum required GPA to get admits into Good Universities ?
and lastly what would be my academic score in terms of GPA for 64%

Pls help me out guys.. even after extensive searching, i couldn't narrow down my GPA ...

no. the unis will surely accept percentage too....if there is no provision, email the grad student reception and ask them wat to do

and u CANNOT convert % to gpa on ur own...its a vast idea. so leave it :) the unis knw how to consider ur % score itself