The GTIN System

Basic Overview

The GTIN is assigned to each pertinent hierarchical level, e.g.:

Unique items must be assigned unique GTINs
Each trade item must have a unique GTIN (e.g., 4 x 8 plywood vs. 2 x 8 plywood, 16 oz. bug spray vs. 32 oz. bug spray)
Retail unit and the case of the product must have unique GTINs (e.g., 16 oz. bug spray vs. a case of 24 cans of 16 oz. bug spray).
Intermediate packages must have unique GTINs (e.g., The packaging within the outer container that may be used as protection against breakage, spillage etc.).
Different case counts of the same product must have unique GTINs (e.g., a retail box of 3/4" screws packed in a case of 50 vs. a case of 100).

Example of a GTIN & an Explanation of Its Structure

Packaging Indicator - indicates the level of packaging (i.e. 1 = pack of 12, 2 = pack of 36, 3 = pack of 48, etc). This number is at the discretion of the manufacturer but must be numbers 1-8.
Zero or First Number of the EAN-13 - This number will be zero unless individual identification uses EAN-13 data structure (if so, this digit will be the first number of the EAN-13).
EAN.UCC Company Prefix - The EAN.UCC Company prefix is the portion of the GTIN that is assigned by the numbering organization of the manufacturer. This number uniquely identifies the manufacturer of the product. This number is of variable length and may differ between manufacturers.
Item Reference Number - The Item Reference Number is used to identify the product. The number of digits for this number will be dependent upon the Company Prefix.
Check Digit - The check digit is a mathematically calculated number based on the previous 13 digits that are in the code.
Bearer Bars - a black line surrounding the four sides of the code. This helps to reduce chances of misreading the bar code.

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