What is variable data printing?

It is only possible digitally. An offset plate is a fixed physical object and every impression from it is identical by definition, so anything that must vary has to be imaged individually. That is why variable data is listed as a digital capability rather than a general one.

The applications divide into two families. Marketing uses it for personalisation, unique promotional codes and versioned campaigns. Industry uses it for identification and traceability: numbered tickets and certificates, asset labels, and — most significantly in this market — serialised codes on pharmaceutical packaging.

That second family carries requirements the first does not. A unique code is only useful if it scans reliably at speed, so the print itself has to be verified rather than assumed. Contrast, quiet zone, substrate absorbency and any varnish over the code area all affect whether a DataMatrix grades. Print quality becomes a compliance question rather than an aesthetic one.

The data side needs as much care as the print side. A clean, validated data file with no duplicates and no gaps is the difference between a straightforward job and an expensive reconciliation exercise, and it is worth agreeing the format before production is scheduled.

Proofing works differently too. You approve the fixed design plus a small set of representative variable records rather than every copy, so it is worth agreeing upfront which edge cases appear on that proof — the longest name, the highest serial number, an optional field left empty. Those are where variable-data jobs break.