Data Matrix Code vs QR code
Data Matrix code and QR (quick response) code came on the market as an upgrade
od old 1D code, due to its possibility to store more data on same size. Both DMC and
QR code share more advantages towards 1D code: level of data correction, readability
angle and small size.
On first sight both codes look very similar, they are both made of dark and bright
squares and are typically square. The main visual difference represents finding
pattern which is in an L symbol at DMC code and three squares at QR code.
Encoding more data on 2D code consequently makes code larger. A Data Matrix bar code can hold up to 2,335 alphanumeric characters and QR Code holds up to 4,296 alphanumeric characters. Accepted dimensions of data matrix code vary from 10×10 modules up to 144×144 modules. The growth is made in steps by 2 modules. The QR code from 21×12 up to 144×144 with growth of 4 modules in each direction.
Data matrix code is believed to be more reliable than QR because of higher Error
Correction level. Percentage of data correction for DMC is around 30% and for QR
codes there are 4 different levels possible: Level L (Low) 7%, Level M (Medium)
15%, Level Q (Quartile) 25% , Level H (High)30% of code words can be restored.
QR codes are commercially more know and are seen on various commercials,
websites, jumbo posters and retail stores. Data matrix code is very commonly used
in industry for marking small components. Most of 2D readers downloaded as mobile
App are capable of reading QR code and some of them are made for reading both. I
will write more about DMC readers in my next post.
Which code should I use?
Which code is better to use depends on various factors, but I can say that if you are looking for commercially use the QR is better choice, because more phone readers supports QR reading. If you are limited with label size and encoded data is smaller than 30 bytes that DMC is a better choice.