Polycrystalline diamond cutters for rotary drill bits and methods of making the same are disclosed. A polycrystalline diamond compact includes a polycrystalline diamond body having a working surface, an interface surface, and a perimeter surface. The polycrystalline diamond compact also includes a substrate bonded to the polycrystalline diamond body along the interface surface. A non-diamond volume fraction of the polycrystalline diamond body is greater at the interface surface than at the working surface.