Chapter 2. Character set encoded in barcodes

Feb 13, 2019

There is a lot to consider when attempting to select an appropriate barcode to use. You should familiarize yourself with the various barcode types, their capabilities, and requirements, to ensure a proper barcode selection for your given scenario. To select the barcode for your given task, you need to understand its character set. There are generally four different types of character sets:

Numeric — A numeric character set includes numbers only (0-9)
Alphanumeric — An alphanumeric character set includes numbers and alphabetic characters (0-9 and A-Z)
GS1 AI encodable character set 82 ⁠— includes numbers (0-9), alphabetic characters (A-Z), and special characters (refer to page 471 of the standard)
Full ASCII — An ASCII character set includes any ASCII character (value 0-127).

Barcode capabilities range anywhere from using dozens of characters to encode with a particular 1D barcode to thousands of characters in 2D barcodes. There are mainly two types of barcodes:

1D barcodes consist of vertical black lines against an all-white background. The lines are of varying widths with specific gaps resulting in a particular pattern.
2D barcodes consist of square or rectangular patterns of two dimensions. Again, the patterns are usually black against an all-white background.

Generally, 2D barcodes store more data and support a bigger character set than 1D barcodes. However, bigger is not always better. Barcode selection should be based on efficiencies of maximizing a character set with a little room to grow rather than perhaps double or triple the character set you may use. Otherwise, this might have an impact on processing speeds. Below is a comparison table of several common barcode symbologies. To learn about more barcode types, you may take a look at the barcode comparison webpage.

	QR Code	PDF417	UPC-A	Code 39	Code 128

Density	High-density	High-density. PDF417 was one of the first publicly available high-density 2D barcodes	Moderate-density. UPC prints bars and spaces in four different widths and takes up half the space of an Interleaved 2 of 5 code.	Moderate-density	High-density
Character set	Full ASCII	Full ASCII	Numeric	Alpha-numeric (Code 39 also support these characters: Percent sign (%), Plus sign (+), Dollar sign ($), Slash mark (/), Period (.), Hyphen (-))	Full ASCII