A GTIN (Global Trade Item Number) is the unique identifier assigned to a trade item—any product or service that is priced, ordered, or invoiced at any point in the supply chain. It is not itself a barcode; rather, it is the number that gets encoded into a barcode so scanners and databases can recognise the item instantly.
If you are choosing barcodes for retail, understanding GTINs is the essential first step before picking a symbology or a supplier.
The four GTIN formats
GTIN is an umbrella term that covers four fixed-length numeric structures:
| Format | Length | Typical use | Common barcode symbology |
|---|---|---|---|
| GTIN-8 | 8 digits | Small items where space is limited | EAN-8 |
| GTIN-12 | 12 digits | Retail items, especially North America | UPC-A |
| GTIN-13 | 13 digits | Retail items, especially outside North America | EAN-13 |
| GTIN-14 | 14 digits | Cases, cartons, and other packaging levels | ITF-14 |
All four share the same core rules: they are globally unique, carry a check digit for error detection, and are managed through the GS1 system. The format you need depends on where you sell, the physical size of your product, and whether you are identifying a single unit or a multipack.
GTIN versus barcode: the number and the symbol
A common source of confusion is the difference between the number and the symbol.
- GTIN is the number itself—the string of digits.
- EAN, UPC, and ITF-14 are barcode symbologies (visual formats) that encode that number into machine-readable bars and spaces.
For example, a product might have GTIN-13 6291041500213. That same number can be carried in an EAN-13 barcode for point-of-sale scanning, or in a GS1-128 barcode for logistics if additional data such as batch number is needed. The GTIN stays constant; the symbology changes to fit the application.
What GTINs identify
GTINs identify trade items at various packaging levels:
- Consumer unit — the individual item a shopper buys (GTIN-8, GTIN-12, or GTIN-13)
- Inner pack — a bundle sold to the consumer, such as a twin pack
- Case or carton — a standard shipping container (GTIN-14)
- Pallet — sometimes identified with a GTIN-14, though SSCC serial shipping container codes are also common
Each level that is traded independently needs its own GTIN. A soft drink sold as a single can, a six-pack, and a 24-can case therefore carries three separate GTINs.
One product, one GTIN—per variant
A fundamental rule of the GTIN system is that each distinct product variant needs its own GTIN. This ensures that every difference a customer or supply-chain partner might care about is captured unambiguously.
Variants that require separate GTINs include:
- Size (e.g., 250 ml versus 500 ml)
- Colour or pattern
- Flavour or scent
- Material composition
- Packaging type (bottle versus tube)
- Language of labelling (if the product is regulated or marketed differently)
- Promotional or multipack configurations
Variants that typically do not need a new GTIN include minor batch-to-batch variations that do not change the product’s essential nature, though some industries (pharmaceuticals, fresh food) have stricter rules.
For guidance on how many barcodes a product line may need, see How many barcodes do I need?
How GTINs are allocated
GTINs are issued through the GS1 system. Businesses typically obtain them by:
- Joining GS1 in their country of operation, receiving a company prefix, and constructing GTINs according to GS1 rules.
- Purchasing from a barcode reseller, which supplies individual GTINs already registered within a valid prefix. Resellers are a common route for small businesses and startups that need only a handful of numbers and prefer lower upfront costs.
Both paths produce valid, unique GTINs. The practical difference lies in ongoing fees, the size of the number pool, and whether certain retailers or platforms require direct GS1 membership. GS1 membership is mandatory for some large retailers; for many online marketplaces and independent stores, reseller GTINs work without issue.
Validating a GTIN
GTINs include a mathematically calculated check digit (the final digit) that catches most common transcription errors. You can verify whether a number is structurally valid using the GTIN validator and check digit calculator.
Validation confirms the number is well-formed; it does not confirm ownership, product details, or whether the GTIN is registered in retailer databases. For broader lookup, the Barcodes Database indexes millions of GTINs with associated product information.
Summary
| Concept | Meaning |
|---|---|
| GTIN | The unique numeric identifier for a trade item |
| GTIN-8 / 12 / 13 / 14 | The four standard lengths for different applications |
| EAN / UPC / ITF-14 | Barcode symbologies that encode a GTIN |
| One variant, one GTIN | Each distinguishable product version gets its own number |