GTIN – Global Trade Identification Number.

This refers to any type of barcode that is used in the Global Retail System., so it covers a variety of barcodes.

The most common GTINs:

GTIN-12:

GTIN-12 refers to UPC-A or UPC-12 barcodes.
These are used on products and are used primarily in the USA and Canada.
Related: EAN-13 vs UPC-A barcodes

GTIN-13:

GTIN-13 refers to an EAN-13 barcode.
These are the most common type of barcode used for retail and is common in all countries.
Related: EAN-13 vs UPC-A barcodes

GTIN-14:

GTIN-14 refers to ITF-14 or TUN Carton Codes.
These are used for cartons of 6 or 12 (or any number) of your product and is used purely for stock tracking by the company. It is based on a UPC-A or EAN-13 barcode so the ITF-14 on a carton corresponds to the EAN-13 on the product inside the box.