GS1 Digital Link

How GS1 Digital Link URIs work -- the standard for encoding product identifiers into web-resolvable URLs.

GS1 Digital Link is a standardized method for encoding GS1 identifiers (GTINs) into web-resolvable URIs, conformant with ISO/IEC 18975. It achieves two goals simultaneously:

Offline identification -- identifiers can be extracted from the barcode without internet access
Online information access -- the URI is a functional web address connecting to digital content

URI structure

https://{domain}/01/{GTIN}/10/{batch}/21/{serial}

Component	Example	Purpose
Domain	`eulabel.eu`	Resolver domain (not part of the identifier)
Primary key (AI 01)	`/01/05601234567890`	GTIN -- the product identifier
Key qualifier (AI 10)	`/10/ABC123`	Batch/lot number
Key qualifier (AI 21)	`/21/1001`	Serial number
Query string	`?linkType=gs1:pip`	Request specific link type

Domain independence

The domain is not part of the product identifier:

https://eulabel.eu/01/05601234567890
https://brand.example/01/05601234567890

Both URIs identify the same product. Identifiers persist independently of any domain, which is essential for ESPR persistence requirements.

Identification granularity

Different levels of identification serve different use cases:

Level	GS1 Encoding	Use Case
Model	GTIN only	Product type identification
Batch	GTIN + lot number	Recall readiness, batch-specific data
Item	GTIN + serial number	Repairs, warranty, individual traceability

Examples

Model level:  https://eulabel.eu/01/09506000164908
Batch level:  https://eulabel.eu/01/09506000164908/10/LOT2025A
Item level:   https://eulabel.eu/01/09506000164908/21/SN00012345

Each level inherits data from above -- everything at the GTIN level applies to all batches and items under it.

Key properties

Globally unique -- no two products share an identifier
Persistent -- identifiers never change throughout the product lifecycle
Web-resolvable -- scan a QR code with any smartphone camera, no app needed
Open standards -- no vendor lock-in, portable across systems
Backward compatible -- same identifiers work in legacy barcode systems

Data carriers

Carrier	Smartphone Support	DPP Suitability
QR Code	Ubiquitous	Primary choice (cited by ESPR)
Data Matrix	Uneven	Good for small/cylindrical products
NFC	Widely implemented	Assessment pending

QR Code with GS1 Digital Link URI syntax is the recommended data carrier for DPP compliance.