Amazon requires that all products listed for sale have a unique product identifier, such as a UPC (Universal Product Code), EAN (European Article Number), or ISBN (International Standard Book Number). These codes are used to identify products and help ensure that product listings are accurate and complete.
There are several websites where you can purchase UPC codes, including GS1, Nationwide Barcode, and Buyabarcode.com.
Of these, GS1 is the most widely recognized and recommended by Amazon, as it is the original source of UPC codes and is the only organization authorized to issue UPCs in the United States.
