A Global Trade Item Number (GTIN) is a number that uniquely identifies a product. You see them beneath the barcodes on almost every product in the world. Which is why they’re often called ‘barcode numbers’. In the UK and Europe they’re usually 13 digits long, in the US 12. You might see shorter 8 digit numbers, used on smaller products. There are even 14 digit versions, to identify cases of products. The same numbers are used to identify products sold online too. The important thing to know is that they are all licensed from GS1 organisations around the world – to guarantee their uniqueness. When you join GS1 UK you can create all the GTINs you need.