On the basis of number of digits and purpose it is used for, GTIN can be classified in 4 formats4
GTIN-8 includes seven digits containing a GS1-8 Prefix and the Item Reference and Check digit. This is a smaller barcode
usually used on small retail trade items. For more information, refer to section 4.3.7 of GS1 General Specifications
This code is encoded in UPC-A barcodes, which are mostly used in USA and Canada. GTIN-12 components include eleven digits containing your U.P.C. Company Prefix and the Item Reference and Check digit. GTIN-13:
This code is also referred to as EAN-13 barcode. This is the most popular GTIN format that is globally utilized for the retail sector. It contains Twelve digits containing your GS1 Company Prefix and the Item Reference, and Check digit. A GS1 Company Prefix used to create a GTIN-13 will begin with a 1-9. GTIN-14:
This barcode is used when the number of goods is of variable measure. It contains the Indicator Digit to indicate packaging level (1-8) or that the product is variable measure, twelve digits containing your GS1 Company Prefix and the Item Reference and Check digit.
Among these four types, GTIN-13 (European Article Number/EAN13) is widely used in India.