Theoretical max dimensions according to its respective specs: BMP (uint32 in go/x/image/bmp): 4,294,967,295 GIF: 65,535 JPEG: 65,535 (65,500 for the libjpeg-turbo based software) PNG: 4,294,967,295 TIFF (uint32 in go/x/image/tiff): 4,294,967,295 libjpeg-turbo max of 65,500 pixels appears to be a good limit for the other image formats, since all known image viewers are getting problems with image dimensions higher than this value, or even at values far smaller than this.