Code 93 is one of the most popular linear barcode symbology designed in 1982 by Intermec Corporation. Code 93 encodes each character using 6 elements packed into 9 modules. The code encoded within code 93 is as follows: a start character, encoded message, first modulo-47 check character “C”, second modulo-47 check character “K”, stop character and termination bar.
Code 93 offers higher information density for alphanumeric data. Code 93 is used primarily by Canadian postal office to encode supplementary delivery information. Code 93 is an alphanumeric, variable length symbology that represents full ASCII character set using combinations of 2 characters. Code 93 is a continuous symbology and produces denser code. Code 93 always includes two check characters which are referred to as "C" and "K". These two check characters immediately follow the encoded message itself and immediately precede the final stop character.
Structure of a code 93 barcode
A typical code 93 barcode includes the following structure:
Code 93 Extended is based on Code 93 and can encode all 128 ASCII characters. The characters represented by Code 93 are represented in Code 93 Extended as single bar code characters, but all other characters are represented by a control character plus another character. You must take this into account when estimating bar code length. Code 93 is more compact version of Code 39. It encodes exactly the same characters as Code 39, but uses 9 barcode elements per character instead of 15. The Modulus 43 checksum is optional, just as with Code 39.