Most of us know that a QR code is a 2D form of barcode seen on product packaging and mobile apps. Its full form is Quick Response, meaning it gives prompt access to the contained information encoded inside.
Apart from being accessible by everyone, these codes have larger data capacity as well as better fault tolerance than the conventional codes. This may arise a few prompts in your mind such as how is information stored in a QR code and how many bytes can be encoded in a QR code. Read on to know more.
The QR Code Structure
A QR code typically features a pattern of random black and white checkers, which seems to be a small puzzle. However, upon close inspection, they actually encompass a few structural parts, which are as follows:
- Positioning: Are corner squares that show the printing orientation of code.
- Alignment: Are random squares that aid with orientation in case of a large code.
- Timing: Are lines in between positioning markers to help scanner in recognizing how big the data pattern is.
- Version: Are around the positioning squares to indicate the version of the code in use (40 versions are available, which answers how many types of QR codes are there. Of these, 1-7 are for marketing)
- FormatInfo: Are around the positioning squares containing the error tolerance and mask pattern details for smooth scanning.
- Data and Error Correction Keys: Cover the rest of the code area and contain the actual data.
- Quiet Zone: Forms the space surrounding outside the square pattern.
For the scanner to read and understand a QR Code as such, the Code must always be square. What’s more there are additional elements ensure that the information is read correctly.
How Much Data Can a QR Code Carry?
A standard version can contain 3 KB of data. A QR code features several rows and columns, the combination of which forms a grid of squares. The max number of columns and rows are 177, which means the maximum number of squares can 31,329 encoding 3 KB data.
The exact arrangement of these little squares allows data encoding. It is responsible for storing more data in the same space than the traditional barcodes. You cannot create a code with any combination of columns and rows. 40 predefined sizes or versions are available to choose from.
For example, Version 1 codes have a 21×21 grid. From the next version, the number of rows and columns rises by four. A grid of 177 rows and columns forms the largest version, 40. If there is a lot of data, a busier or stuffier look featuring tightly packed squares is evident.
The basic structure of these codes discussed above does not reduce the volume of data to be stored. The only exception here is error correction. The higher its level, the less data is stored in the code. It is a myth that changing the code’s surface area can give way to more data because that cannot increase the columns and rows. It only stretches the structure.
3 KB of data is the answer to how many bytes can be encoded in a QR code. Understanding the different parts is the answer to how is information stored in QR codes.