May 19, 2022

ISBN is an abbreviation (acronym) for International Standard Book Number. A type of international standard code (number system) provided for identifying books (books) and materials. Expressed in Arabic numerals. The Chinese translation name in Japan is "International Standard Book Number". It was developed by a project by WHS Smith, England in 1966 (cf.).


In the United Kingdom in 1965, a book-specific code called SBN (Standard Book Number) was developed by Gordon Foster of Trinity College (University of Dublin). The background is that computers have become widespread and unified control numbers have been required. It began to be used in the UK the following year. In 1967, the algorithm of the international standard ISBN was devised. ISBN was adopted by the International Organization for Standardization (ISO) in 1970 (ISO 2108). In addition to ISBN, the international standards of the International Organization for Standardization for publications (books) include the International Standard Serial Number (ISSN) assigned to each series of serials (magazines).


ISBN is generally applied to various books (books, comics, etc.), as well as publications such as CD-ROMs, cassette tapes, microfilms, etc. that are published by publishers and distributed by publishing agents and bookstores. However, in Japan and other countries, magazine codes are used instead of ISBN for magazines other than Mook. In addition, websites, advertisements, games, etc. are not subject to ISBN internationally. ISBNs are assigned different numbers if they have the same content but different publication formats. For example, if a novel is released in three forms: a book, a paperback book, and an e-book, it will be given a different number. Even if it is out of print, ISBN will not be reused for new publications.

Old standard (until December 31, 2006)

ISBNs are represented by a 10-digit code and usually consist of 4 parts. This 10-digit (old standard) ISBN code may be called ISBN-10 as opposed to the current 13-digit ISBN. ISBN-10 is ISBN ● --AAAA --BBBB --C is displayed. However, the number of digits to be allocated for each part of ●, A, and B is not fixed, and each part increases or decreases within the range of 9 digits in total (10 digits if the C part of 1 digit is always included). The meaning of each part is ● Part- "Group symbol" The country, region, and language area in which the publication was published. The number of digits depends on the number of publications in the group. The minimum is 1 digit and the maximum is 5 digits. See the current standard for the code table. Part A-"Publisher Symbol" The number of digits varies depending on the number of publications of the publisher. In the case of Japan, it is 2 to 7 digits. Part B-"Title symbol" A unique number for the publication. As a general rule, it is given for each edition of the book. Determined for each publisher. In order to allocate the remaining digits of the group symbol / publisher symbol, the number of digits of the title symbol defines the maximum number of possible publication points for each publisher. Publishers that have run out of title symbols will be given a new publisher symbol. Part C-"Check Digit" Inspection numbers. This is to make sure that there are no mistakes when inputting. 0-9, X is used. (X represents the number 10)

Check Digit (until 2006)

The check digit of the old standard ISBN (ISBN-10) is calculated by a calculation method called "modulus 11 weight 10-2". (Multiply the left digit excluding the check digit by 10, 9, 8 ... 2 to get the sum. Divide the sum by 11 and subtract the remainder from 11.) Here, as an example, let's find the check digit (□ part) of ISBN4-10-109205- □. 4x10