How to tell if Gucci bags are real or fake. This guidance is applied to most lines of Cucci bags, including Lophidia, Dionysus, GG Marmont, Supreme & Retro, etc. You can also visit the official website of Gucci and apply the information from this tutorial to help you check important details of the authentification of luxury Gucci bags. The easiest way to tell if a Gucci bag is real or fake is to judge by its appearance. You can check the serial number on the leather plate, the shape of trademark and letters of Gucci Logo on the bags, the appearance of metal zipper, the double-G metal logo in the front, the washing labels, the metal button, etc.