When uploading a design to our design tool, it is always best to select the highest resolution images possible. We support both vector and raster images. We recommend uploading .AI, .EPS and .PDF vector images, though only if the design was initially created as a vector .PNG and .JPG files will work as well.
For best results, we recommend a resolution of at least 1500 x 1500 pixels. Also, make sure to upload photos or images without gradients to stay under our 8 color limit on each product side.
Check out our guidelines for uploading an image for more in depth information.