GS1 Digital Link Explained: One QR for POS and Phone

Marketing wants one QR on the front of the new pack. It needs to open the product page on the brand site when a shopper scans it with their phone. IT wants a different QR on the back of the pack — the one carrying the GTIN that the Sunrise-ready till will scan. Procurement looks at both and asks if maybe the back-of-pack QR could be the front-of-pack QR, since that's one less thing to print. That's the conversation GS1 Digital Link exists to settle: a single 2D barcode whose value is a URL that the phone can open AND the POS can parse for a GTIN.

This guide walks through how the URL is built, which Application Identifiers go in the path versus the query string, when a brand needs its own resolver, and how a Sunrise-ready POS actually pulls the GTIN out of what looks, to anyone else, like a normal web link.

The Short Answer

A GS1 Digital Link is a URL whose path follows a GS1-defined grammar. The path segments encode an Application Identifier and its value — /01/<GTIN> for the GTIN itself, optionally followed by qualifiers such as /10/<batch> in the path and data attributes such as ?17=<expiry> in the query string. Render that URL as a QR Code (the consumer default) or a Data Matrix (the industrial default) and the same symbol works as a shopper-facing URL and as a GS1 carrier for retail POS.

Anatomy of a GS1 Digital Link URL

Take the URL embedded in the QR above and walk through it piece by piece:

https://id.gs1.org/01/05012345678900/10/ABC123?17=261231

• https://id.gs1.org — the resolver domain. Any HTTPS-capable hostname works; id.gs1.org is the canonical community-run resolver that returns brand-supplied content for any registered GTIN.
• /01/05012345678900 — the primary key, here AI 01 (GTIN) followed by the 14-digit GTIN value; other keys such as SSCC (00) and GLN (414) take the same position. UPC-A and EAN-13 are left-padded to 14 digits when they sit in a Digital Link path.
• /10/ABC123 — a qualifier: AI 10 (batch / lot), value ABC123. Qualifiers narrow the identity to a specific production batch.
• ?17=261231 — a data attribute in the query string: AI 17 (expiry date), YYMMDD encoded.

The full grammar is in the GS1 Digital Link standard. The two things to remember in practice: a product URL puts /01/<GTIN> after the resolver host (and after any path the brand adds in front of it), key qualifiers follow as /AI/value pairs in a fixed order, and data attributes go in the query string.

Path AIs vs Query AIs

Not every Application Identifier belongs in the path. GS1 splits AIs into two roles inside a Digital Link:

The split is part of the syntax, not a style choice: key qualifiers sit in the path in the order 22, 10, 21 after the GTIN, and data attributes such as dates go in the query string. A URL that puts a data attribute in the path is not a valid GS1 Digital Link URI, and a conformant parser can reject it.

Custom Resolver Domains

The resolver domain is whatever lives between https:// and the first path segment. id.gs1.org is the canonical resolver — it works for any GS1-issued GTIN and returns content registered by the brand owner. Many brands instead stand up their own resolver at their own domain.

# Canonical GS1 resolver (always works)
https://id.gs1.org/01/05012345678900

# Brand-owned resolver (same grammar, owned domain)
https://yourbrand.com/p/01/05012345678900

# Either URL is a valid GS1 Digital Link — POS pulls
# 05012345678900 from the /01/ path segment in both.

A brand-owned resolver is a thin web service that answers any /01/<GTIN>… request and either redirects to the right product page or returns the content directly. The work is in three parts: standing up the service, mapping every GTIN to a destination, and (for traceability) reading the AIs that arrived alongside the GTIN. Several SaaS vendors offer this off the shelf; the open-source Digital Link Toolkit from GS1 covers the parsing rules if you're building your own.

Rendering as QR or Data Matrix

The symbology is independent of the payload. Both QR Code and Data Matrix can carry a Digital Link URL of any length within their respective capacity limits.

To prototype either form for proofing, use the GS1 Digital Link Generator. It builds the URL from a GTIN plus AIs and renders both the QR and the Data Matrix from the same payload.

How POS Extracts the GTIN

When a Sunrise-ready POS scans a GS1 Digital Link QR, it doesn't open the URL. It parses the URL locally and reads the path:

1. The scanner decodes the QR to a string. The string starts with https:// (or http:// for some older resolvers).
2. The POS application strips the scheme and host, leaving a path like /01/05012345678900/10/ABC123.
3. It walks the path in pairs: AI 01 means the next segment is a GTIN-14, AI 10 means the next segment is the batch, and so on. The grammar is deterministic, so no schema lookup is needed.
4. The extracted GTIN goes into the same lookup pipeline that a 1D EAN feeds; the till posts the price, the back-office picks up the batch / expiry.

To verify a URL parses cleanly, paste it into the decoder. The same input feeds into the same logic POS uses:

GS1 Digital Link Decoder: Parse any GS1 Digital Link URL into structured GTIN + AI data. Decode the worked example →

Common Mistakes

Most broken Digital Links come from a few encoding errors that a test decode catches before the artwork goes to print.

• Confusing a marketing QR with a Digital Link. A QR opening https://yourbrand.com/campaign isn't a Digital Link — there's no /01/ path segment for POS to grab a GTIN from. Both can sit on the pack; only the Digital Link form is Sunrise-ready.
• Padding the GTIN wrong. The path segment expects 14 digits. UPC-A (12 digits) and EAN-13 (13 digits) are left-padded with zeros. Get the padding wrong and POS reads a different (or invalid) GTIN.
• Encoding dates in the wrong format. Date AIs use YYMMDD — six digits, no separators. Encoding 17=2026-12-31 instead of 17=261231 breaks the parse.
• Putting data attributes in the path. Dates, weights and other data attributes belong in the query string; written as path segments they make the URL invalid, and a conformant parser can reject it. Keep qualifiers in the path and data attributes in the query.
• Putting the resolver behind a redirect. A Digital Link URL needs to be the one printed on the pack. A redirect to a marketing URL works for the phone but loses the AI structure for POS.

Quick Decision Guide

For most brands the answer is the GS1 resolver, a QR Code on consumer packs and a decode test before press.

• Default resolver: https://id.gs1.org/01/<GTIN>…. Always works, costs nothing, perfectly Sunrise-compliant.
• Branded resolver: stand one up only if you want analytics, brand voice or to enrich the page with batch-aware content. Not required for Sunrise.
• Carrier choice: QR for any consumer-facing pack (phone scans matter). Data Matrix for pharma / industrial when symbol size dominates.
• Validate before press. Build the URL with the Digital Link Generator, decode it back with the Digital Link Decoder, confirm POS will extract the right GTIN and AIs.

GS1 Digital Link Resolver

A GS1 Digital Link resolver is the web server at the URL's host name. It reads the GS1 identifiers in the request path and redirects the visitor to a page linked to that product, batch or item.

1. The phone opens the URL and sends a request to the resolver host.
2. The resolver reads the primary key, such as the GTIN, and any qualifiers such as the lot or serial number.
3. It looks up the links the brand registered for that identifier and picks the default one, unless the request asks for a specific link type.
4. It answers with an HTTP redirect, and the browser loads the target page.

Link types let one code serve several destinations. Adding linkType=gs1:pip to the query string asks for the product information page, and other types in the GS1 Web Vocabulary cover destinations such as instructions or recall status.

Because qualifiers are part of the request, a resolver can treat batches differently. A brand can send one recalled lot to a recall notice while every other lot of the same GTIN still opens the normal product page.

Before testing a redirect, paste the URL into the GS1 Digital Link decoder to see exactly which identifiers the resolver will receive.

GS1 Digital Link Standard and Specification

The GS1 Digital Link standard defines how GS1 identification keys and Application Identifiers are written as web addresses. The AIs themselves, with their lengths and data formats, come from the GS1 General Specifications.

GS1 publishes the GS1 Digital Link syntax and the rules for conformant resolvers as separate documents, and refines details between editions, so check the current release on gs1.org before you build a parser or a resolver. The syntax document sets out:

• Which GS1 keys can start the path, including the GTIN (01), SSCC (00) and GLN (414).
• Which qualifiers may follow each key, and in which order.
• Which AIs are data attributes that belong in the query string.
• How reserved characters inside a value must be percent-encoded.

GS1 Digital Link Format

The GS1 Digital Link format puts the parts in a fixed sequence: scheme and host, an optional path of the brand's own, the primary key, its qualifiers, then the query string.

https://example.com/01/09506000134352/10/ABC1/21/12345?17=271231

For a GTIN, the qualifier order is consumer product variant (22), then batch or lot (10), then serial number (21). Any of them can be left out, but the order cannot change, and a URL with only the GTIN is already complete.

A QR code with GS1 Digital Link encodes this whole string unchanged. The GS1 Digital Link generator follows this layout, placing lot and serial in the path and expiry, best-before and net weight in the query string.

Key takeaways

• A GS1 Digital Link is a URL whose path follows a GS1 grammar — one 2D barcode serves the shopper's phone and the Sunrise-ready POS.
• Path AIs (qualifiers) identify the product variant; query AIs (data attributes) carry per-unit data like expiry.
• id.gs1.org is the default resolver; a branded resolver is optional and doesn't change Sunrise compatibility.
• QR is the consumer default; Data Matrix is the industrial default — both carry the same Digital Link URL.
• Validate every Digital Link payload with the decoder before sending artwork to press — the URL grammar is unforgiving once it's been printed.

References

• GS1 Digital Link standard — the canonical document defining the URL grammar, qualifier / attribute split and resolver behaviour. Published by GS1.
• GS1 General Specifications — the AI table that the path segments draw from: gs1.org/standards/barcodes.
• GS1 "2D at POS" — Sunrise 2027 milestones that make Digital Link the default consumer-pack 2D carrier: gs1.org/standards/barcodes.

Need to ship a Digital Link tomorrow? Build one with the GS1 Digital Link Generator, decode it with the GS1 Digital Link Decoder, and match the Sunrise context in the Sunrise 2027 page.

Frequently Asked Questions