What are QR Codes?

An explanation of QR Codes

A QR code (abbreviation for Quick Response code) is a specific matrix barcode (or two-dimensional code) that is readable by dedicated QR barcode readers and camera phones. The code consists of coloured (usually black) modules arranged in a square pattern on a white background. The information encoded may be text, web site or other data.

Common in Japan, where it was created by Toyota subsidiary Denso-Wave in 1994, the QR code is one of the most popular types of two-dimensional barcodes. The QR code was created to allow its contents to be decoded at high speed.

Although initially used for tracking parts in vehicle manufacturing, QR codes now are used in a much broader context, including both commercial tracking applications and convenience-oriented applications aimed at mobile phone users (termed mobile tagging). QR codes may be used to display text to the user, to add a vCard contact to the user’s device, to open a website, or to compose an e-mail or text message. You can generate and print your own  own QR codes for free here.

How does it work?

A user would take their reading device most likely a mobile phone with a camera and scan (take a picture) of the code with an application designed to read QR codes – here’s our recommended QR Code applications. This application then reads and interprets the data to provide the information contained. The process is easy you can see our demonstration here.

Technical Diagram of a QR Code


How much data can they hold? - click to view


QR Codes can hold a lot of data which is why they are so useful however pushQR minismises the data in the code for faster more accurate scanning and stores the data in our engine.

Numeric code Max. 7,089 characters
Alphanumeric Max. 4,296 characters
Binary (8 bits) Max. 2,953 bytes
Kanji/Kana Max. 1,817 characters

What is their ability to deal with errors? - click to view


QR Codes can be generated with teh ability to deal with scenarios where some of the QR code image is disturbed. This make them very robust.

Level L 7% of codewords can be restored.
Level M 15% of codewords can be restored.
Level Q 25% of codewords can be restored.
Level H 30% of codewords can be restored.