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The Global Language of Business

Release 1.0.0, Sept 2026

GS1 online technologies: how they fit together

A guide to GS1 Digital Link URIs, linksets, link types, resolvers and the GS1 Web Vocabulary

GS1 Digital Link URIs, linksets, link types, resolvers and the GS1 Web Vocabulary are complementary parts of a standards-based approach to sharing data with search engines, AI agents and other software used by consumers. Together, they help connect GS1 identifiers to information that is provided by, or endorsed by, the issuer of the identifier. That information can be discovered, understood and used by people and software.

GS1 identifiers, such as a Global Trade Item Number (GTIN) or a Global Location Number (GLN) are encoded in a Web-compatible form known as a GS1 Digital Link URI. There should always be an intermediate step between the identifier of a "thing" and the location of information about the thing. This 'redirection' can be achieved manually or via software of some sort. If multiple sources of information about an item are available, any number of links can be provided in a machine-readable list known as a linkset. The type of information available at each link is provided using a link type. A GS1-conformant resolver provides a standardised method for software to access the entire linkset or for a query to be directed to a specific link within it.

If the links in the linkset lead to data that has been expressed using the GS1 Web Vocabulary, this creates a distributed model in which data owners can publish and maintain their own data, complete with a machine-readable guide to its meaning for maximum interoperability.

This guideline is intended primarily for GS1 Member Organisation staff who need to explain how several GS1 online technologies work together as parts of a coherent whole. It is not an implementation guide and does not repeat the detailed requirements found in the relevant standards. Instead, it provides a common explanation of the roles played by GS1 Digital Link URIs, linksets, link types, the resolver and the GS1 Web Vocabulary, and points readers to the documents that define them in detail.

In order to present a coherent narrative that includes all the different terms like link type and resolver, this document sets out how all those features fit together. It should be emphasised however that use of a resolver is not required for all cases. See Connecting barcodes to related information for an overview of the available choices [REL]. Linksets and link types can be used independently of a resolver, however, to keep the content of the document manageable, we will assume use of all of the available components of the GS1 online technology suite.

GS1 identifiers already help industry identify products, locations, assets, shipments and more in a globally consistent way. Online technologies extend that value by making it easier for people and softSelche Datenware to find trustworthy information about the things identified by GS1 keys.

The technologies discussed here are based on Linked Data principles. In simple terms, Linked Data uses Web identifiers so that things and the data about them can be named, looked up and connected to other things. The W3C summary describes Linked Data as a set of best practices for publishing structured data on the Web:

This approach matters because it allows data to be distributed. Data owners can publish and maintain their own data, while still making it discoverable through common Web standards. That is important for scale: no central organisation has to keep a copy, host or control every piece of data that may be relevant to a product, place, asset or organisation. Data is always up to date as it is managed at source, by the data owner, without having to rely on third party data management.

It also matters because knowledge graphs, search engines and Large Language Models all benefit from being able to discover reliable, structured data with clear provenance. Better data supports better consumer experiences and reduces the risk that AI will 'hallucinate' and produce inaccurate or invented answers.

This becomes more important as commerce is increasingly mediated by Artificial Intelligence: from generating product descriptions to acting as consumers’ agents in discovering, comparing and purchasing goods. The more reliable and machine-readable the underlying data, the better those systems can serve consumers and businesses.

Verifiable Credentials are also part of the wider Linked Data family. They are not the focus of this document, but they are relevant to the same strategic direction. Verifiable Credentials can allow GS1, brand owners, certificate scheme owners, assessment bodies and others to make assertions about products, locations and assets, with cryptographic proof of authorship, at scale, and without relying on centralised databases or always-on APIs.

A GS1 Digital Link URI expresses GS1 identifiers in a Web address. It allows a GS1 identification key, such as a GTIN or GLN, to be used in a way that can be scanned, read by systems and opened on the Web [DL-URI].

It is important to be clear that GS1 Digital Link does not create a new kind of identifier. A GTIN is a GTIN and a GLN is a GLN, whatever syntax or data carrier is used. GS1 Digital Link URIs encode GS1 identifiers using GS1 Application Identifiers, just like other GS1 syntaxes. The same identifier may appear in GS1 element strings in a GS1 DataMatrix, in an EPC RFID tag, or in a GS1 Digital Link URI encoded in a QR Code or Data Matrix.

This distinction is essential. The URI is a Web-friendly expression of the identifier; it is not simply the address of a product information page. The identified thing and the location of information about that thing are separate. Redirection, or an equivalent discovery mechanism, is therefore commonly used to connect the identifier to one or more useful resources [REDIRECTION] [REL].

A single scan may need to support many different journeys. A consumer may want ingredients, allergens, promotions or recycling instructions. A retailer may want stock or availability information. A regulator may want compliance information. A patient or clinician may want healthcare product information. An engineer may want installation or service history for an asset.

One possible response is to put all information in one place, but that approach quickly becomes difficult to govern and maintain. A better approach is to allow the GS1 identifier to act as a stable starting point from which different relevant resources can be discovered.

The document Connecting barcodes to related information [REL] describes several ways to link a single GS1 barcode to multiple sources of information. Only one of those methods uses a GS1-Conformant resolver. This is an important point: a resolver can be very useful, especially where machine-discoverable links and multiple resource types are needed, but it is not a prerequisite for every GS1 Digital Link implementation [REL].

A linkset is a machine-readable list of links associated with a resource. The IETF linkset standard defines formats for representing sets of links as standalone documents [LINKSET].

In the GS1 context, a linkset can be understood as a structured list of places where information or services related to an identified thing can be found. For example, it may include links to a product information page, instructions, sustainability information, traceability information, certification information or a brand owner API.

Linksets are useful because they separate the identity of the thing from the many resources that may describe, support or provide services for that thing. They are also useful because they can be read by software, not just by people.

A list of links, a linkset, is only useful if the purpose of each link is clear. Link types provide that meaning. They say what kind of relationship exists between the identified thing and the linked resource.

For example, one link may point to product information, another to instructions, another to certification information and another to traceability information. The linked content and the target URLs themselves (the locations of the actual information) may change over time, but the link type explains why each link is relevant in a machine-readable way.

GS1 link types are defined within the GS1 Web Vocabulary. They are used both as link relation types in links and linksets, and as properties in Linked Data statements. This means the same GS1-defined relationship can be used consistently in Web links and in structured data [WEBVOC].

A GS1-Conformant resolver is a service that accepts GS1 Digital Link URIs and resolves the GS1 identification keys within them to one or more sources of related information or services as set out in a linkset [RESOLVER].

A resolver is especially valuable when a single identifier needs to support different responses depending on context, such as the requested link type, language, media type or other attributes. It makes links discoverable by software in a standardised way.

However, a resolver should be presented as one approach, not as the only approach. GS1 Digital Link URIs can be connected to online information through simple redirection, landing pages, linksets and other patterns as described in GS1 guidance [REDIRECTION] [REL]. The key principle is that the GS1 identifier remains stable while the locations of related information can be managed over time.

The GS1 Web Vocabulary provides a shared set of terms for describing products, organisations, places and related concepts using Linked Data. Rooted in GDSN, it extends the world's most used vocabulary, schema.org. Where relevant, the GS1 Web Vocabulary makes mappings and relationships to schema.org explicit [WEBVOC].

The vocabulary helps data publishers use common terms when describing things identified by GS1 keys. It supports structured data that search engines, knowledge graphs, apps and other software can process more reliably.

The GS1 Web Vocabulary is published in JSON as Linked Data (hence the name "JSON-LD"). The underlying data is the definitive machine-readable resource, and individual terms can also be accessed through persistent URLs on ref.gs1.org. For example, the term Product has its own persistent URL (https://ref.gs1.org/voc/Product), while the data behind that human-readable page is part of the vocabulary dataset [WEBVOC].

The same publishing pattern is increasingly used elsewhere in GS1 resources. The GS1 glossary is now also published from JSON-LD, with individual glossary terms available through persistent URLs. This makes it easy to link to the GS1 definition for terms like GTIN and syntax in any document, spreadsheet or presentation.

The main components described in this guideline work together as follows.

Together, these technologies support a distributed model for trusted data sharing. The identifier remains stable. The data can be held and maintained by the appropriate data owner. The links between the identifier and relevant resources can be discovered. The meaning of those links and data elements can be interpreted consistently.

When explaining these technologies to members and solution providers, Member Organisations should emphasise the following points.

GS1 Digital Link URIs, linksets, link types, resolvers and the GS1 Web Vocabulary should be presented as complementary parts of one coherent approach, not as separate or competing technologies. Each has a distinct role, but their value is greatest when they are understood and used together.

These technologies help industry move away from isolated product pages and proprietary integrations towards a more scalable, distributed and trustworthy data ecosystem. That ecosystem supports better information for consumers, more flexible data sharing for businesses, and stronger foundations for search, knowledge graphs and AI-mediated commerce.

[DL-URI]
GS1 Digital Link Standard: URI Syntax. https://ref.gs1.org/standards/digital-link/uri-syntax/. This standard is now synonymous with the term "GS1 Digital Link". Mark Harrison, Peta Ding, Phil Archer. GS1 Ratified Standard. January 2021 & subsequent editions.
[GLOSSARY]
The GS1 Glossary can be browsed and each term may be linked to at https://ref.gs1.org/glossary.
[HOW-WHY]
The How and Why of GS1 Digital Link. https://ref.gs1.org/docs/2021/HowAndWhy_GS1_Digital_Link. A history of the ideas that underpin these technologies. Phil Archer, GS1, November 2021.
[LINK TYPES]
The full list of ratified link types, part of the GS1 Web Vocabulary, is at https://ref.gs1.org/voc/?show=linktypes. A JSON file of the same data is always available at https://ref.gs1.org/voc/data/linktypes
[LINKED-DATA]
W3C Wiki: Linked Data. https://www.w3.org/wiki/LinkedData.
[LINKSET]
RFC 9264: Linkset: Media Types and a Link Relation Type for Link Sets. https://www.rfc-editor.org/rfc/rfc9264.html E. Wilde, H. Van de Sompel, RFC 9264. IETF July 2022.
[QR-BP]
Best practices for creating your QR Code powered by GS1. https://ref.gs1.org/docs/2023/QR-Code_powered-by-GS1-best-practices. A good place to start when talking to brands and retailers about 2D barcodes.
[QUICK-START]
Quick start guide for GS1 Digital Link. https://ref.gs1.org/docs/2024/digital-link-quick-start-guide. Aimed primarily at a technical audience, it sets out the design principles behind GS1 Digital Link, including why some AIs go in the path and some in the query string.
[REDIRECTION]
Redirection: from scan to content. https://ref.gs1.org/docs/2024/redirection-from-scan-to-content. How this essential feature can be implemented.
[REL]
Connecting barcodes to related information. https://ref.gs1.org/docs/2024/connecting-barcodes-to-related-information. This is the key document that sets out how a single QR Code powered by GS1 can fulfil multiple functions.
[RESOLVER]
GS1-Conformant Resolver Standard. https://ref.gs1.org/standards/resolver/ Phil Archer. GS1 Ratified Standard, February 2024 & subsequent editions.
[WEBVOC]
GS1 Web Vocabulary. https://ref.gs1.org/voc/ (for humans) and https://ref.gs1.org/voc/data/gs1Voc.jsonld (for machines). Erik Kauz, Mark Harrison, Dan Wilde. GS1 Ratified Standard. 2014 onwards.
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