The GTIN (Global Trade Item Number) is a unique identifier for trade items developed by GS1. A trade item is any product or service that can be priced, ordered, or invoiced. This number can be used to identify products globally and is commonly found in retail, appearing as barcodes on product packaging. The GTIN can have varying lengths (8, 12, 13, or 14 digits) depending on the type of product and where it's sold. For instance, the 12-digit version is known as a UPC (Universal Product Code) and is prevalent in North America. In the sneaker resell market, the GTIN is crucial. Authenticating sneakers often involves verifying their GTIN to ensure the product matches the official release. By referencing a GTIN, resellers can ascertain specific details about the sneaker, such as its official name, colorway, and size. This helps in ensuring authenticity, streamlining inventory management, and facilitating sales across various platforms. For someone just starting in sneaker reselling, recognizing and utilizing the GTIN can aid in avoiding counterfeit products and in building a trustworthy reputation in the market.