The four GTIN lengths
A GTIN is a number, not a barcode. The same GTIN can be carried by different barcodes depending on where the item is scanned: a retail product usually has EAN-13 or UPC-A, while a case might use ITF-14 or GS1-128, and a medicine pack might use GS1 DataMatrix.
In databases GTINs are usually stored as 14 digits, with shorter GTINs padded with leading zeros, so every length fits one field.
- GTIN-8: small packs, carried by EAN-8
- GTIN-12: carried by UPC-A, used mainly in the US and Canada
- GTIN-13: carried by EAN-13
- GTIN-14: packaging levels such as cases, often carried by ITF-14
Where GTINs come from
Companies get GTINs by licensing a company prefix from a GS1 member organization in their country, then numbering their own products under that prefix. Retailers and online marketplaces often check that a product’s GTIN matches the brand owner’s registered prefix.
GS1 publishes allocation rules for when a change to a product needs a new GTIN, for example a change in declared net content or a new variant a shopper would want to tell apart.
GTINs in 2D codes
The GTIN carries over into 2D codes. In a GS1 DataMatrix it appears after Application Identifier (01), and in a QR code using GS1 Digital Link it appears in the web address, such as https://id.gs1.org/01/09506000134352.