HSN (Harmonized System of Nomenclature) code is a 6 to 8-digit standardized numerical method used globally to classify over 5,000 products for trade and taxation. Developed by the World Customs Organization (WCO), it ensures uniform classification, eases international trade, and determines GST rates in India. To find the HSN code of a product, use the official GST Portal under 'Services' > 'User Services' > 'Search HSN Code'. Enter the product name, keywords, or the first few digits to get the 4, 6, or 8-digit code along with its GST rate.