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Field of Application

ISBN-Numbers are international order numbers for books. For books they have a similar importance as the EAN Code for food. They are managed in Germany by "Börsenverein des deutschen Buchhandels" (Tel. 069/13060).

A ISBN code is created by using an EAN-13 code with the prefix "978".

 

Charset / Number of Characters

ISBNs are made up of the prefix "978" plus 9 usable digits 0..9 and a checkdigit. The checkdigit can be the digit 0..9 or the character "X". The character "-" is used to separate country code, publishers code, book number and checkdigit. The separator is ignored by the barcode library.

 

Checkdigit

A checkdigit is required and is also included in the label. The barcode library can generate the checkdigit automatically. If an erroneous checkdigit is provided, the barcode library treats this as an error and no barcode is painted.

The algorithms for the checkdigit generation are differently between EAN and ISBN. With the ISBN algorithm it can happen that the checkdigit "10" is computed, which is represented by an "X", for example "3-928444-00-X". The barcode library does not allow to leave out the "X" or to replace it by another character.

 

Characteristics

•The label below the barcodes contain the ISBN coded as EAN-13 and above the barcode as text in clear, including the checkdigit.

•The ISBN barcode is a special variation of the EAN-13 code. Often it is used in conjunction with the EAN-5 add-on code, for example for the quotation of prices. In the example above it is DM 19.80 (or whatever currency).