Overview of International Standard Serial Number (ISSN)

The ISSN (International Standard Serial Number) is an international code number to identify "serials* and other continuing resources**". A particular ISSN corresponds to a particular media version of a serial or other continuing resource. The ISSN is defined by the international standard (ISO 3297) and its corresponding national standard (JIS X 0306).

The ISSN is a simple eight-digit identification number consisting of a seven-digit number plus a check digit. The eighth (last) digit number serves to prevent typographical errors and in some cases is replaced by the capital letter "X".

Unlike the ISBN (International Standard Book Number), the ISSN is a simple identification number without any meaning attached.

The National Diet Library (NDL), which acquires national serial publications exhaustively as the only national and deposit library in Japan, plays a role as the Japanese National Centre for ISSN.

* A serial is defined as a publication, in any medium, that meets all the following criteria:

• -Issued in a succession of discrete issues or parts (i.e., published continuously under a unique title and separately in volumes, etc.)
• -Bearing numbering (e.g., a volume, number, issue, month, year, etc.)
• -With no predetermined conclusion

Example： Periodicals, newspapers, monographic series, etc.

** A continuing resource is defined as a publication, in any medium, that is issued over time with no predetermined conclusion and made available to the public. Continuing resources include serials and ongoing integrating resources***.

*** An integrating resource is defined as a publication, either finite or with no predetermined conclusion, that is added to or changed by updates that do not remain discrete and are integrated into the whole and made available to the public in any medium version.

Example: Loose-leaf publications, databases, etc.

From the viewpoint of bibliographic records, serials and other continuing resources need continuous correction: i.e., they often undergo changes in their titles, publishers, frequency of publication, etc.

To gain accurate information on serials and other continuing resources in spite of their nature and vast number is an important but challenging task for users, libraries, publishers, publication distributors, and vendors alike. In response, publishers and libraries draw upon computers to manage information on serials and other continuing resources and facilitate the distribution and use of them.

Consequently, it has become necessary to identify serials by their code numbers, and the ISSN (International Standard Serial Number) is a widely recognized numbering system for serials and other continuing resources. The foremost advantage of ISSN is that any serials and other continuing resources with an ISSN can be easily identified irrespective of its publishing country, publisher, language, or genre.

Online catalogs or databases of libraries and some platforms of online journals are equipped with a search field for ISSN and it helps users to find and obtain a specific serial or other continuing resource. Citations in an article can also include ISSN so that readers can easily find each cited work.

The ISSN is used to increase the efficiency of receiving, photocopying, lending, and indexing serials at libraries and placing orders, receiving and other business operations of publishers and book stores with a faster speed and greater accuracy. Furthermore, since ISSN are registered in an international database maintained by the ISSN International Centre, Japanese serials and other continuing resources will have greater opportunities for overseas circulation.

The assignment of an ISSN to a continuing resource does not imply any meaning or legal evidence with regard to the ownership of rights to that publication or its contents.

A key title is a unique title created for registration of an ISSN. It establishes an inseparable one-to-one correspondence between each serial or other continuing resource and its ISSN.

Like an ISSN which is a unique number, a key title is also unique: i.e., one key title cannot be shared by more than one publication.

Once assigned to a publication, an ISSN will never be reused in another publication even if the first publication becomes defunct.

If the key title must be changed, the ISSN of the publication is also changed irrespective of the reasons for change such as the merger or split of serials and other continuing resources.

Key titles are established by the ISSN Network in accordance with its cataloging rules.

Applicants are informed of the ISSN and the key title by the formal notice of ISSN (only in Japanese) sent by the Japanese Centre.

* The key title is the Romanized form of the title proper (=main title) of a serial or other continuing resource. In the case of a title proper in a Western language (Latin characters), in principle, the key title is identical with the title proper. If there are more than one publication which share the same title proper, the one which is registered later will have qualifying information.

Example:　 "国際子ども図書館の窓"

The key title of print edition: Kokusai Kodomo Toshokan no mado

The key title of online edition: Kokusai Kodomo Toshokan no mado (Online)

If a publication has its key title in a Western language, the abbreviated key title is also recorded. Abbreviations are made according to the List of Title Word Abbreviations maintained by the ISSN International Centre.

ISSN-L is an abbreviation for Linking ISSN. If a publication is published in more than one media format, they share the same ISSN-L though the ISSN assigned for each format differ from each other. An ISSN-L is the same as one of the ISSN for the publications which share the same ISSN-L.

Example:　"National Diet Library newsletter"

Print edition:　 ISSN 0027-9161   ISSN-L 0027-9161

Online edition: ISSN 1344-7238   ISSN-L 0027-9161

The ISSN Network* is an international organization promoting the exchange of information on serials and other continuing resources among ISSN National Centres with the ISSN International Centre (Paris, France) serving as the data bank.

The ISSN Network consists of the ISSN International Centre and ISSN National or Regional Centres located in various countries. The bibliographic data for publications with ISSN, which is assigned by each ISSN Centre, is finally registered to the database called the ISSN International Register. This database is maintained by the ISSN International Centre and contains all the authorized records. Bibliographic data for serials that have been registered ISSN are made available to the public via the ISSN Portal.

* The ISSN Network was created as part of the UNISIST (World Science Information System) which was established in 1967 through the resolution of the UNESCO general conference. In 1971 the ISO formulated a draft ISSN standard, followed in 1972 by the establishment of an international serials registration centre in Paris by the concerted effort of UNESCO and the French government.
UNESCO member nations were invited to create their own domestic or regional registration centres in order to expand the serials registration data to the world size. As of September 2023, the ISSN Network embraced 93 National Centres.

Here is the link to the ISSN Manual used commonly in the ISSN Network:

• To the page of ISSN Manual (opens in another window)

For the details of the ISSN International Centre and the ISSN Network, please refer to the web page of the ISSN International Centre (in English and five other languages).

• To the page of the ISSN International Centre (opens in another window)

The NDL took over becoming a Japanese National Centre for ISDS ("ISDS" is the former name of the ISSN Network, International Serials Data System) in 1973, and has actively served as the Japanese National Centre for ISDS since January 1976. The name changed to Japanese National Centre for ISSN in 2002. As of the end of 2022, the Japanese National Centre for ISSN manages about 48,000 bibliographic records for serials with ISSN. They are included in the over 2.2 million records registered in the ISSN International Register.

The Japanese Centre is in charge of the assignment and management of the ISSN for publications published in Japan. As its daily work, the Japanese Centre also corrects the data of the registered ISSN, for example, corresponding with changes to serials and other continuing resources (i.e., change of publisher or editor, suspension or end of publication). In addition, when a publication with a changed key title is found, the Centre also advises the publisher to acquire an ISSN. If a publisher fails to display their assigned ISSN, the NDL prompts them to do so.

The Japanese National Centre for ISSN cannot achieve its full mission of promoting the ISSN Network without the cooperation of publishers. It is essential that publishers actually display the assigned ISSN on their serials and other continuing resources and that, whenever planning to start a new publication or to change the title, the publishers notify the Japanese National Centre in advance. For this purpose, the NDL and publishers need to maintain close communication, and the NDL seeks all-out cooperation from government agencies, universities, academic societies, and other libraries.

After July 2013, similar to the legal deposit system but for print or packaged electronic publications, the National Diet Library collects and preserves online publications published by the private sector such as e-books and e-magazines. Online resources with ISSN fall into the category of e-periodicals "granted specific codes (ISBN, ISSN, DOI)," which are subject to the legal deposit system.

For the details of deposits of online publications, please refer to the FAQ.

Japanese National Centre for ISSN
Serials and Non-book Materials Division, Acquisitions and Bibliography
Department, National Diet Library
Fax: +81-3-3581-1330
E-mail: issnjpn