A packaging line in South Africa usually prints or applies three linear barcodes and, more and more, a 2D code: EAN-13 on the consumer unit, ITF-14 or GS1-128 on the outer case, GS1-128 with an SSCC on the pallet label, and a GS1 DataMatrix or QR code where more data or a web link is needed. This series explains each in plain words, with the GS1 size rules, and what a line check can and cannot prove.
What this series covers
Barcodes on a packaging line answer three different questions: which product is this (the GTIN), which batch and date does it carry, and which logistic unit is this case or pallet (the SSCC). GS1, the standards body behind retail barcodes, sets which symbol carries which data (GS1 General Specifications 2026). GS1 South Africa describes EAN and UPC as printed on nearly every consumer product, and GS1-128 and ITF-14 as the barcodes that track items through the supply chain (GS1 South Africa, barcode types).
Each chapter covers one symbol: where it is used, what it carries, the GS1 size and placement rules, how a fixed code reader or a smart camera reads it on the line, and the faults we see most. How print quality is graded to ISO/IEC standards is a separate question, covered in the barcode quality standards series.
Retail is moving towards 2D codes that carry more than a product number (GS1, 2D barcodes), and GS1 South Africa promotes 2D barcodes in retail (GS1 South Africa). The last two chapters cover those.
Chapters
- 01What is an EAN-13 barcode, and what can a line check on it?The till barcode on consumer units: GTIN-13 and its check digit, GS1 sizes and placement, faults, and how a line checks it. · 8 min
- 02What is an ITF-14 barcode, and why does it fail on cases?The case barcode printed on corrugated board: GTIN-14, GS1 sizes and placement, the bearer bar, print faults and reading at the case packer. · 8 min
- 03What is a GS1-128 barcode, and how does it carry an SSCC?Application Identifiers and FNC1, the SSCC and the GS1 logistic label, sizes and placement, and what a dispatch line checks. · 9 min
- 04What is GS1 DataMatrix, and how is it different from Data Matrix?The small 2D code that carries GTIN, batch and dates: structure, GS1 sizes, capacity, print faults and line reading. · 8 min
- 05QR codes on packaging: what a line can checkPlain QR, GS1 QR and GS1 Digital Link, GS1 sizes, the retail move to 2D, print faults, and what a line check proves. · 8 min
Which barcode goes where?
The choice follows the packaging level and the data the next scanner needs. GS1 says barcodes for different GTINs must never be visible on one item, so each level carries its own code and the unit codes inside a case should not be readable through it (GS1 General Specifications, 6.2.1).
| Packaging level | Usual symbol | What it carries | Where it is read on your line | Chapter |
|---|---|---|---|---|
| Consumer unit sold at the till | EAN-13 (GTIN-13) | Product number only | After labelling or carton forming, before grouping | EAN-13 |
| Consumer unit, extra data | GS1 DataMatrix or QR with GS1 Digital Link, beside the EAN-13 | GTIN plus batch, expiry, serial | Directly after the coder that prints it | GS1 DataMatrix, QR codes |
| Outer case, number only | ITF-14 (GTIN-14) | Case GTIN only | After the case packer or case coder | ITF-14 |
| Outer case with batch or dates | GS1-128 on a label | GTIN, batch, dates as AIs | After the case labeller | GS1-128 |
| Pallet or other logistic unit | GS1-128 with AI (00) on a GS1 logistic label | SSCC; often contents, count, batch, dates | After the pallet labeller, before dispatch | GS1-128 and SSCC |
GS1 sizes and quality at a glance
Every symbol has a minimum and maximum module size, a minimum height for linear codes, a quiet zone and a minimum print grade, set in the GS1 symbol specification tables for each scanning environment (GS1 General Specifications, 5.12.3). The table summarises the rows packaging lines use most; each chapter gives the detail and the exceptions.
| Symbol | X-dimension (module) | Minimum bar height | Quiet Zone | Minimum quality |
|---|---|---|---|---|
| EAN-13, till only | 0.264 to 0.660 mm (target 0.330) | 18.28 to 45.70 mm, by X | 11X left, 7X right | 1.5/06/660 |
| EAN-13, till and distribution | 0.495 to 0.660 mm | 34.28 to 45.70 mm | 11X left, 7X right | 1.5/06/660 |
| ITF-14, distribution | 0.495 to 1.016 mm | 31.75 mm | 10X each side | 1.5/10/660; 0.5/20/660 direct on corrugate |
| GS1-128, pallet label | 0.495 to 0.940 mm | 31.75 mm | 10X each side | 1.5/10/660 |
| GS1 DataMatrix, retail item | 0.396 to 0.990 mm | Set by data | 1 module all round | 1.5/12/660 |
| QR with GS1 Digital Link, retail item | 0.396 to 0.990 mm | Set by data | 4 modules all round | 1.5/12/660 |
The quality column reads as grade, measuring aperture in thousandths of an inch, and light wavelength in nanometres. Grade 1.5 corresponds to ANSI letter grade C and 0.5 to D (GS1 General Specifications, Table 5-43). A line reader does not measure these grades; a verifier does.
Where does a line read each code?
Most packaging lines have three natural reading points, one per packaging level. Each reader decodes the code, parses the data, compares it with what the line is running and rejects a mismatch, with a sensor confirming the reject.
Swipe sideways to see the whole drawing →
| Checkpoint | Code | What the reader checks | What it cannot prove |
|---|---|---|---|
| A · Unit, after labelling or coding | EAN-13; 2D code if printed | Present, readable, GTIN = product running; batch and date in the 2D code = run data | Print grade; that the artwork is legally correct |
| B · Case, after case packing or coding | ITF-14 or GS1-128 | Case GTIN (not the unit GTIN); batch and dates if in GS1-128 | That the case holds the right count of the right units |
| C · Pallet, after labelling | GS1-128 with SSCC | Every barcode on the label read; SSCC new and recorded; contents and count = pallet built | That the wrapped pallet is physically complete |
Carton and pallet verification and label inspection cover the stations; choosing a code reader covers the reader.
Why do codes that read on the line fail later?
- Wrong content, perfect print. The wrong artwork, label or coder data after a changeover. Only a comparison with the expected GTIN, batch or SSCC catches it.
- Print quality on the edge. A close, well-lit line reader is forgiving; a distribution centre scanner at distance is not. Falling decode margins on the line are the early warning.
- Size and quiet zone. Artwork squeezed below the GS1 minimum, or a quiet zone cut by a seam, flap or text.
- Data structure. A missing FNC1 separator in GS1-128, or a plain Data Matrix where a GS1 DataMatrix is expected: the code reads, the receiving system misreads.
- Two codes for two GTINs. A unit code readable through the case or shrink film.
Why barcodes that scan are still rejected at the distribution centre works through these with the retailer’s view.
What South African suppliers are asked for
Many South African retailers require a GS1 South Africa barcode test report as a mandatory step in product listing. GS1 South Africa tests to ISO 15416 methods and checks compliance with GS1 standards, size, colour, print quality and numbering; it accepts final packs, artwork, labels and packaging, and issues a final or an interim report (GS1 South Africa verification service). That report covers samples. A line reader covers every pack after the run starts, which is why most suppliers need both.
On 2D, GS1 supports industry’s ambition to read 2D barcodes at retail points of sale by the end of 2027 (GS1 General Specifications, 1.2.2.2.1), and GS1 South Africa reports Woolworths and selected suppliers already using GS1 2D barcodes (GS1 South Africa, 2D in retail). For a line, that turns fixed artwork into variable data printed per batch, which needs checking like a date code.
Questions about barcodes on packaging lines
Which barcode goes on the product, the case and the pallet?
Usually EAN-13 on the consumer unit, ITF-14 or GS1-128 on the outer case, and GS1-128 carrying an SSCC on the pallet label. Your retailer’s requirements and GS1 South Africa’s guidance decide the details for your products.
Can one camera read all of these codes?
A fixed code reader or a smart camera with code tools reads linear and 2D codes in one field of view, provided the codes face the reader and are large enough for its resolution. Units, cases and pallets pass different points on the line, so they usually have their own readers.
Does reading a barcode on the line prove it meets GS1 quality?
No. Reading proves the code decodes and its content is right; grading to ISO/IEC 15416 or 15415 needs a verifier and a defined method. A line reader can flag codes that read poorly, which is an early warning, not a grade.
What is the smallest barcode GS1 allows?
It depends on the symbol and where it is scanned. An EAN-13 for till-only items can go down to a 0.264 mm X-dimension; ITF-14 and GS1-128 for distribution start at 0.495 mm; 2D codes on retail items start at 0.396 mm per module.
Will 2D codes replace EAN-13 in South Africa?
Not yet. GS1 requires 2D codes on retail items to be in addition to the linear barcode during the transition, with an industry ambition of 2D scanning at the till by the end of 2027.
Sources
- GS1 General Specifications, Release 26.0 (Jan 2026), GS1 South Africa copy (standard, checked 2026-10-27)
- GS1: 2D barcodes (standards body page, checked 2026-10-03)
- GS1 South Africa: 2D in retail (standards body page, checked 2026-10-27)
- GS1 South Africa: barcode verification service (standards body page, checked 2026-10-27)
- GS1 South Africa: barcode types (standards body page, checked 2026-10-27)
Have a line in mind?
Describe the product and the fault you need to catch. We test on your samples and reply with a feasibility note and a budget.