A photonic fanout die has a planar structure that has a top surface, a bottom surface, and outer side surfaces extending between the top surface and the bottom surface around an outer perimeter of the planar structure. The planar structure includes an opening formed within the outer perimeter. The opening has side surfaces that extend from the top surface to the bottom surface. The photonic fanout die also includes a plurality of optical waveguides formed within the planar structure to extend from a side surface of the opening to an outer side surface of the planar structure. The plurality of optical waveguides is configured such that a spacing between adjacent optical waveguides at the outer side surface of the planar structure is greater than a spacing between adjacent optical waveguides at the side surface of the opening.