QR Code vs Data Matrix
Both are 2D matrix barcodes, but Data Matrix codes are typically used for very small industrial and pharmaceutical labeling where extreme density matters, while QR codes dominate consumer-facing uses because of universal smartphone camera support and instant visual recognizability.
Data Matrix codes can pack a similar amount of data into an even smaller physical footprint than a QR code, which is why they show up etched onto tiny electronic components or printed on medication blister packs. What they don't have is the QR code's three-corner finder pattern, which makes QR codes easier for an untrained eye to spot and trust as "scan me."
For anything aimed at a general consumer — a menu, a poster, a business card — a QR code is almost always the right choice specifically because people already recognize it on sight.
Structurally, Data Matrix uses an "L"-shaped solid border along two adjacent sides instead of three separate corner squares, which is part of how it achieves a smaller minimum footprint than QR at comparable data amounts — there's simply less structural overhead dedicated to positioning markers relative to the data area.
Industrial and pharmaceutical use cases favor Data Matrix specifically because components and packaging in those industries are often marked using direct laser etching or dot-peen marking rather than ink printing, and Data Matrix's design tolerates the lower-contrast, physically etched marks that process produces better than a QR code's finer three-corner pattern typically would at the same tiny scale.
Neither format is objectively "better" — they were built to solve different problems. QR optimizes for fast, reliable recognition and decoding by an ordinary phone camera at consumer scanning distances. Data Matrix optimizes for maximum data density in the smallest possible physical space, aimed at dedicated industrial scanners reading codes that are often only millimeters across.