Chanel serial stickers ran from 1986 to 2021: 7 digits through 2005 (the first digit is the series), then 8 digits (the first two digits are the series), then the April 2021 switch to metal plates and microchips with randomized codes. Enter the serial; the tool answers in the honest year range and checks it against the selected model's documented history.
The serial dates the bag's production window. It does not authenticate anything: superfakes carry good-looking stickers with matching cards, so the code is where inspection begins, never where it ends. Bags made before 1986 carry no serial at all, and absence on true vintage is not damning. From April 2021 the plates and chips are randomized and public charts stop; for those bags the maison's own verification and physical inspection are the record. Resale authenticators also flag serials beginning 176, 177 or 178 for extra scrutiny, after blank stickers from that era were stolen. A serial whose era disagrees with the model's documented history is itself a finding.