A PNG file is a Portable Network Graphics file. The format uses lossless compression and is generally considered the replacement for the GIF image format. PNG files store graphics on websites. Some ...

$ file iphone-id.png iphone-id.png: PNG image data, 470 x 118, 8-bit/color RGB, non-interlaced Where identify really shines is with JPEG files, which the file command can't quite seem to figure out.

How to convert PNG to JPG on Mac. You can save PNG files as JPGs in a number of common Mac apps, but the easiest is to use Preview. 1. Start Finder and then locate the PNG file you want to convert. 2.