The preferred file format for uploading premium icons in is SVG. We are finding that customers are not downloading or buying PNG icons. We will accept PNG icon in special circumstances such as highly-rendered 3D icons but, in general, we no longer accept PNG icons.
When you upload SVG files, we will convert them to PNG as well as ICNS, ICO, CSH, AI and IconJar.
What icon size do you support?
Most icons are designed in increments of 8 pixel sizes, but we have no restrictions on the sizes of the actual icons. Read more about Sizes.