QR code labels and batch traceability

A QR code on a label is no longer a gadget. It's the link between the physical product and everything that doesn't fit on the pack: product sheet, batch origin, instructions, promos, complaint form. Digital print lets every label in a run carry a different code at no extra tooling cost. Below, what matters in practice.

Minimum size and contrast

• Minimum 12 × 12 mm for reliable phone scanning at 10-15 cm. Below 10 mm the failure rate rises visibly.
• Real contrast: dark code on light background. White QR on metallic or on clear film without an opaque white underneath won't scan.
• Quiet zone of at least 4 modules around the code, with no text or frame touching it.
• Avoid heavy gloss lamination directly over the code if the product sits under shelf lighting - reflection blocks the camera. Matte is safer.

Variable data: how to deliver the content

For unique per-label codes (serialisation, promo codes, batches) you send a CSV or XLSX with one column per variable field and one row per label. We map the columns into the layout and generate the codes at print time. The file order becomes the roll order, so if you need an ascending sequence for an applicator, tell us in the brief.

What link sits behind the code

Practical rule: never bake the final URL into the code. Use a redirect you control (your own subdomain). If you change the destination page a year later, already printed labels keep working. Without a redirect, one site restructure turns your entire stock into dead codes.

Batch traceability without a complex system

• One QR per batch (not per unit) covers most food and cosmetics traceability requirements with minimal effort.
• Batch, production date and shelf life can be printed digitally in the run, with no later manual stamping.
• For distribution control or anti-counterfeiting, go with a unique code per unit plus a list of valid codes on your side.