QR code vs Data Matrix, Aztec and PDF417
QR is the 2D barcode everyone knows, but it is not the only one. Data Matrix, Aztec and PDF417 are just as standardised and are everywhere — on medicine packs, boarding passes and driving licences. Here is how to tell them apart and when each is used.
How to recognise them
- QR code — square, with three large "eye" squares in three corners.
- Data Matrix — square or rectangular, with a solid L-shaped border on two sides and a dotted (alternating) border on the other two. No corner eyes.
- Aztec — square, with a single bullseye of nested squares in the centre.
- PDF417 — a wide rectangle made of stacked rows of short bars, with start and stop patterns on the left and right edges.
- Micro QR — a small QR-like square with only one eye.
Side by side
| Symbology | Standard | Max capacity (approx.) | Typical use |
|---|---|---|---|
| QR code | ISO/IEC 18004 | 7,089 digits · 4,296 alphanumeric · 2,953 bytes | Phones: links, Wi-Fi, payments, menus |
| Data Matrix (ECC 200) | ISO/IEC 16022 | 3,116 digits · 2,335 alphanumeric · 1,556 bytes | Pharmaceuticals, electronics, parts marking, GS1 DataMatrix |
| Aztec | ISO/IEC 24778 | 3,832 digits · 3,067 alphanumeric · 1,914 bytes | Mobile boarding passes, rail and transit tickets |
| PDF417 | ISO/IEC 15438 | 2,710 digits · 1,850 text characters · 1,108 bytes | Driving licences and ID cards, printed boarding passes, shipping |
| Micro QR | ISO/IEC 18004 | 35 digits · 21 alphanumeric | Very small labels, components |
Capacities are the largest symbol size with the least error correction; real symbols hold much less.
Data Matrix
Data Matrix packs data very densely and stays readable when printed extremely small or marked directly onto metal and plastic with a laser or dot-peen tool, which is why it dominates industrial part marking. Its GS1 variant, GS1 DataMatrix, carries product identifiers, batch numbers and expiry dates on medicine packaging; in the EU, the Falsified Medicines Directive requires a Data Matrix code with a unique serial number on most prescription medicines. Error correction is Reed-Solomon, like QR, but with a fixed level per symbol size.
Aztec
Aztec Code was invented in 1995 by Andrew Longacre Jr. at Welch Allyn. Because the finder is in the middle, it needs no quiet zone around the edge, and it reads well from a phone screen — reasons it is common on mobile boarding passes and rail tickets. The airline industry's IATA boarding-pass standard allows Aztec, QR, Data Matrix and PDF417.
PDF417
PDF417 ("Portable Data File", with 4 bars and spaces in each 17-module-wide codeword) was developed at Symbol Technologies in 1991. It is a stacked linear code: rows of barcode on top of each other, readable by line-scanning laser readers as well as cameras. It is the barcode on the back of US and Canadian driving licences (AAMVA standard) and on many printed boarding passes.
Micro QR and rMQR
Denso Wave also defined smaller QR family members. Micro QR uses a single finder pattern and sizes from 11×11 to 17×17 modules, for tiny parts with short payloads. rMQR (rectangular Micro QR, ISO/IEC 23941) is a long thin rectangle for narrow spaces such as cable labels or the edge of a package. Phone cameras generally don't read either — they are for industrial scanners.
Which should you use?
- For people with phones — QR. It is the only 2D code that phone camera apps universally act on.
- For tiny industrial marking — Data Matrix, or what your industry's GS1 application standard specifies.
- For tickets and IDs — whatever the issuing system requires (often Aztec or PDF417).
Retail is also moving toward 2D: GS1's "Sunrise 2027" programme aims for point-of-sale scanners to read 2D codes such as QR codes carrying a GS1 Digital Link alongside traditional barcodes by the end of 2027. For the classic 1D comparison, see QR code vs barcode.
Make a standard QR code
The format every phone camera reads — generated free in your browser.
Open the generatorFrequently asked questions
What is the difference between a QR code and a Data Matrix code?
A QR code has three square finder patterns in its corners; Data Matrix has an L-shaped solid border and a dotted border. Data Matrix is denser and favoured for small industrial and pharmaceutical marking, while QR is the format phone cameras read.
Can my phone scan Data Matrix, Aztec or PDF417?
Phone camera apps are built around QR codes. Other 2D symbologies usually need a dedicated scanner app or an industrial reader.
Why do boarding passes use Aztec or PDF417?
The IATA boarding-pass standard allows Aztec, QR, Data Matrix and PDF417. Aztec reads well from screens and needs no quiet zone; PDF417 can be read by older laser scanners at gates.
Is a QR code a 2D barcode?
Yes. QR codes, Data Matrix, Aztec and PDF417 are all 2D (two-dimensional) barcodes; PDF417 is technically a stacked linear code.