ISBN – Wikipedia

The International Standard Book Number (ISBN) is a number used to uniquely identify books and other independent publications with an editorial component, such as multimedia products.

Until the end of 2006, the number range of an ISBN had ten digits including a check digit. As there were difficulties in Eastern Europe and the English-speaking world in assigning numbers to new publishers and publications, a revised ISO standard for the new 13-digit ISBN was introduced at the beginning of 2005. Old ISBNs in the ten-digit format are now referred to as ISBN-10.

The ISBN-13 consists of five groups of numbers. It is coded as follows:

• The prefix is 978 or 979 depending on the book – there was no prefix for ISBN-10.
• The group number (also known as the country number) is a code for a national, geographical, language or other suitable group. It is defined by the international ISBN agency and can contain different numbers of digits. In the example, it is 3 for German-language.
• The publisher number is a code for the publisher. It is assigned by the national or regional ISBN agency. For Germany, this is the Marketing- und Verlagsservice des Buchhandels in Frankfurt am Main, for Austria the Hauptverband des Österreichischen Buchhandels in Vienna and for Switzerland the Schweizer Buchhändler- und Verleger-Verband in Zurich. The publisher number can contain different numbers of digits. Which publisher numbers are valid depends on the group number, see Weblinks.
• This is followed by the title number assigned by the publisher (also known as the volume number). The publisher (or printer, etc.) is free to use any number, only the number of digits is determined by the publisher number (eight digits in total), but different products must be differentiated, i.e. separately sold volumes, different bindings and so on. There is no rule regarding the treatment of editions.
• Finally, a check digit is given.

GC Wizard offers the following check digit tools for ISBNs