It’s been awhile since we took a closer look at a bar code symbology, so today I’m going to provide information about code 128. Code 128 is a high-density alphanumeric symbology that is capable of encoding the entire ASCII character set from ASCII 0 to ASCII 128. Much like Code 39, Code 128 is capable of encoding a wide selection of characters, but is much more compact. Code 128 is designed to use the least amount of space for data with 6 characters or more of any 1D bar code. This makes Code 128 ideal for industries where label size is an important factor, such as the shipping and packaging industries.
Code 128 has three different subsets that are indicated by three separate start characters. Subset A is capable of encoding alphanumeric characters, control characters and special characters. Subset B allows encoding of all standard alphanumeric characters, plus the lower case alphabet and special characters. And finally, Subset C compresses two digits into each character creating a much denser symbol.
Most bar code scanners easily scan code 128 by default and this symbology is a standard on nearly all varieties of barcode printing software.