GS1 and 2D barcode glossary

2D barcode

A barcode that encodes data in two dimensions rather than one, allowing far more data in the same area. QR Code and Data Matrix are the two symbologies relevant to retail packaging, and GS1 approves three specific configurations of them for point of sale.

Application Identifier (AI)

A two to four digit prefix in GS1 data that declares what the following characters mean. AI 01 is the GTIN, AI 10 is a batch or lot number, AI 17 is an expiry date. Application Identifiers are what let one barcode carry several distinct pieces of data unambiguously.

Data Matrix

A square 2D barcode symbology defined in ISO/IEC 16022. It packs data into a smaller area than a QR Code, which is why it is favoured in healthcare and on small regulated packaging. It is not readable by most consumer phone cameras by default, so it suits supply chain and regulatory use rather than consumer engagement.

Dual marking

Carrying both a traditional linear barcode and a 2D barcode on the same package during the transition. The default recommendation, because the checkout keeps working regardless of how quickly a given retailer upgrades. Migration guide.

EAN/UPC

The GS1 family of retail point-of-sale linear barcodes, comprising EAN-13, EAN-8, UPC-A and UPC-E. EAN-13 is the 13 digit form used across most of the world, and UPC-A the 12 digit form familiar in North America. Modern retail scanners read all of them, and each carries a GTIN.

GS1

The global not-for-profit standards organisation that maintains GTINs, barcode symbologies and the GS1 Digital Link standard. National member organisations, such as GS1 Canada, license identifiers to companies in their territory. GS1 Canada and retailer readiness.

GS1 DataMatrix

Data Matrix ECC 200 carrying GS1 Application Identifier element strings. This is the GS1 variant, and it is one of the three 2D formats GS1 approves for retail point of sale, alongside Data Matrix and QR Code carrying a GS1 Digital Link URI.

GS1 Digital Link URI

A web address that carries GS1 identification keys in the structure defined by the GS1 Digital Link URI Syntax standard, for example a path containing /01/ followed by the GTIN. A browser treats it as an ordinary URL. A point-of-sale application that has been updated for it can extract the GTIN from it. What is GS1 Digital Link?.

GTIN

Global Trade Item Number. The number that identifies a product. It is what a UPC, an EAN and a QR Code carrying a GS1 Digital Link URI all carry. Changing the barcode symbology does not change the GTIN.

Linear barcode

A one-dimensional barcode made of parallel bars, read by a laser or imaging scanner. UPC and EAN are the familiar retail examples, and each carries a single GTIN. Other linear symbologies such as GS1 DataBar Expanded and GS1-128 can carry additional data including batch number and expiry date, using Application Identifiers.

Point of sale (POS)

The checkout system that scans the product and looks up its price. Sunrise 2027 is fundamentally a target for these systems: they are the thing that has to become able to read 2D barcodes.

QR Code

A square 2D barcode symbology readable by ordinary phone cameras. That consumer readability is why it, rather than Data Matrix, is the symbology usually discussed for consumer-facing retail packaging. QR Code is a registered trademark of DENSO WAVE INCORPORATED.

Quishing

Phishing carried out through a QR code, including the physical attack of placing a malicious sticker over a legitimate printed code. Documented on parking meters, payment terminals and public signage, and an argument for keeping destinations on a domain you control.

Resolver

A service that receives a GS1 Digital Link URI and returns links to the online resources associated with that identifier, either redirecting to one or returning the full set. GS1 defines conformant behaviour in the GS1-Conformant Resolver Standard, separately from the GS1 Digital Link URI Syntax standard that defines the address itself. In practice it is also what lets you change a destination without reprinting packaging. Bilingual packaging.

Sunrise 2027

The GS1 industry initiative targeting the end of 2027 for retail point-of-sale systems to be able to scan 2D barcodes, alongside existing linear barcodes. A readiness target, not a law, and not a switch-off date for the UPC. GS1 Canada calls the same initiative Ambition 2027. What Sunrise 2027 is and is not.

UPC

Universal Product Code. The linear barcode symbology used in North American retail since the 1970s, part of the GS1 EAN/UPC family. UPC-A carries a 12 digit GTIN-12, and UPC-E is a truncated form of it. Nothing about the 2027 target requires removing it from packaging.

Reference material: the GS1 General Specifications, the GS1 Digital Link URI Syntax standard and the GS1-Conformant Resolver Standard. QRbolt is listed by GS1 Canada as a solution provider, which is a directory listing rather than an endorsement or a certification.