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.
Understanding GTINs is the essential first step before picking a barcode symbology and a barcode 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 comply to a standard managed by GS1. 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 symbology for point-of-sale scanning, or in a GS1-128 barcode symbology 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
New GTINs are issued for use through a governing body. Today that is the GS1 system but there were others in the past (GTINs have existed since the 1970’s but GS1 was formed in the early 2000’s). Businesses typically obtain them by:
- Paying GS1 membership fees in their country of operation, receiving a company prefix, and allocating GTINs to products from a number range assigned to them by GS1. Usually involves annual recurring fees to continue using the GTIN.
- Purchasing from a barcode reseller, who sells legally acquired unused GTINs from a valid prefix allocated for use by one of the prior issuing bodies (non-GS1 allocated GTINs). Resellers are a common route for small businesses and startups that need only a handful of numbers and prefer single one-off costs and 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 most marketplaces and independent stores, reseller GTINs work without issue as the numbers all comply to the same underlying standard.
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. Indeed, there is no single global database that records all GTINs and all products, only many databases of various sizes and reputability. 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 |