
An International Standard Serial Number (ISSN) is an eight-digit to
uniquely identify a
periodical publication
Periodical literature (singularly called a periodical publication or simply a periodical) consists of Publication, published works that appear in new releases on a regular schedule (''issues'' or ''numbers'', often numerically divided into annu ...
(periodical), such as a magazine.
The ISSN is especially helpful in distinguishing between serials with the same title. ISSNs are used in ordering, cataloging, interlibrary loans, and other practices in connection with serial literature.
The ISSN system was first drafted as an
International Organization for Standardization
The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries.
M ...
(ISO)
international standard
An international standard is a technical standard developed by one or more international standards organizations. International standards are available for consideration and use worldwide. The most prominent such organization is the International O ...
in 1971 and published as ISO 3297 in 1975. ISO subcommittee
TC 46/SC 9
ISO/TC 46 is Technical Committee 46 of the International Organization for Standardization (ISO), responsible for matters concerning information, indexing and documentation.
The scope of the committee is 'standardization of practices relating to li ...
is responsible for maintaining the standard.
When a serial with the same
content is published in more than one
media type
In information and communications technology, a media type, content type or MIME type is a two-part identifier for file formats and content formats. Their purpose is comparable to filename extensions and uniform type identifiers, in that they ide ...
, a different ISSN is assigned to each media type. For example, many serials are published both in
print and
electronic media
Electronic media are media that use electronics or electromechanical means for the audience to access the content. This is in contrast to static media (mainly print media), which today are most often created digitally, but do not require ele ...
. The ISSN system refers to these types as print ISSN (p-ISSN) and electronic ISSN (e-ISSN). Consequently, as defined in ISO 3297:2007, every serial in the ISSN system is also assigned a linking ISSN (ISSN-L), typically the same as the ISSN assigned to the serial in its first published medium, which links together all ISSNs assigned to the serial in every medium.
Code format
An ISSN is an eight-digit code, divided by a hyphen into two four-digit numbers.
The last digit, which may be zero through nine or an X, is a
check digit
A check digit is a form of redundancy check used for Error detection and correction, error detection on identification numbers, such as bank account numbers, which are used in an application where they will at least sometimes be input manually. It ...
, so the ISSN is uniquely represented by its first seven digits. Formally, the general form of the ISSN (also named "ISSN structure" or "ISSN syntax") can be expressed as follows:
where
N
is in the set , a decimal digit character, and
C
is in ; or by a
Perl Compatible Regular Expressions (PCRE)
regular expression
A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" ...
:
For example, the ISSN of the journal ''
Hearing Research
The ''Hearing Research'' is a peer-reviewed monthly journal that publishes research work with basic peripheral and central auditory mechanisms.
Indexing and abstracting
According to the ''Journal Citation Reports'', the journal has a 2017 impact ...
'', is 0378-5955, where the final 5 is the check digit, that is
C
=5. To calculate the check digit, the following algorithm may be used:
To confirm the check digit, calculate the sum of all eight digits of the ISSN multiplied by their position in the number, counting from the right. (If the check digit is X, add 10 to the sum.) The remainder of the sum modulo 11 must be 0. There is an online ISSN checker that can validate an ISSN, based on the above algorithm.
In EANs
ISSNs can be encoded in
EAN-13 bar codes with a 977 "country code" (compare the 978 "
bookland
"Bookland" is the informal name for the Unique Country Code (UCC) prefix allocated in the 1980s for European Article Number (EAN) identifiers of published books, regardless of country of origin, so that the EAN namespace can catalogue books by ...
" country code for
ISBN
The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase or receive ISBNs from an affiliate of the International ISBN Agency.
A different ISBN is assigned to e ...
s), followed by the 7 main digits of the ISSN (the check digit is not included), followed by 2 publisher-defined digits, followed by the EAN check digit (in most cases, this will not match the ISSN check digit, since they are each calculated in a different way).
Code assignment, maintenance and look-up
ISSN codes are assigned by a network of ISSN National Centres, usually located at
national libraries
A national library is a library established by a government as a country's preeminent repository of information. Unlike public libraries, these rarely allow citizens to borrow books. Often, they include numerous rare, valuable, or significant ...
and coordinated by the ISSN International Centre based in
Paris
Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...
. The International Centre is an
intergovernmental organization
Globalization is social change associated with increased connectivity among societies and their elements and the explosive evolution of transportation and telecommunication technologies to facilitate international cultural and economic exchange. ...
created in 1974 through an agreement between
UNESCO
The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
and the French government.
Linking ISSN
''ISSN-L'' is a
unique identifier
A unique identifier (UID) is an identifier that is guaranteed to be unique among all identifiers used for those objects and for a specific purpose. The concept was formalized early in the development of computer science and information systems. ...
for all versions of the serial containing the same
content across different media. As defined by ''ISO 3297:2007'', the "linking ISSN (ISSN-L)" provides a mechanism for collocation or linking among the different media versions of the same continuing resource. The ''ISSN-L'' is one of a serial's existing ISSNs, so does not change the use or assignment of "ordinary" ISSNs; it is based on the ISSN of the first published medium version of the publication. If the print and online versions of the publication are published at the same time, the ISSN of the print version is chosen as the basis of the ''ISSN-L''.
With ''ISSN-L'' is possible to designate one single ISSN for all those media versions of the title. The use of ''ISSN-L'' facilitates search, retrieval and delivery across all media versions for services like
OpenURL
An OpenURL is similar to a web address, but instead of referring to a physical website, it refers to an article, book, patent, or other resource within a website.
OpenURLs are similar to permalinks because they are permanently connected to a r ...
,
library catalogue
A library catalog (or library catalogue in British English) is a register of all bibliographic items found in a library or group of libraries, such as a network of libraries at several locations. A catalog for a group of libraries is also ...
s,
search engine
A search engine is a software system that provides hyperlinks to web pages, and other relevant information on World Wide Web, the Web in response to a user's web query, query. The user enters a query in a web browser or a mobile app, and the sea ...
s or
knowledge base
In computer science, a knowledge base (KB) is a set of sentences, each sentence given in a knowledge representation language, with interfaces to tell new sentences and to ask questions about what is known, where either of these interfaces migh ...
s.
Register
The International Centre maintains a database of all ISSNs assigned worldwide, the ''ISDS Register'' (International Serials Data System), otherwise known as the ''ISSN Register''. the ISSN Register contained records for 1,943,572 items. The Register is not freely available for interrogation on the web, but is available by subscription.
* The print version of a serial typically will include the ISSN code as part of the publication information.
* Most serial websites contain ISSN code information.
* Derivative lists of publications will often contain ISSN codes; these can be found through on-line searches with the ISSN code itself or serial title.
*
WorldCat
WorldCat is a union catalog that itemizes the collections of tens of thousands of institutions (mostly libraries), in many countries, that are current or past members of the OCLC global cooperative. It is operated by OCLC, Inc. Many of the O ...
permits searching its catalog by ISSN, by entering "issn:" before the code in the query field. One can also go directly to an ISSN's record by appending it to "", e.g
n2:1021-9749 – Search Results This does not query the ISSN Register itself, but rather shows whether any WorldCat library holds an item with the given ISSN.
Comparison with other identifiers
ISSN and
ISBN
The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase or receive ISBNs from an affiliate of the International ISBN Agency.
A different ISBN is assigned to e ...
codes are similar in concept, where ISBNs are assigned to individual
book
A book is a structured presentation of recorded information, primarily verbal and graphical, through a medium. Originally physical, electronic books and audiobooks are now existent. Physical books are objects that contain printed material, ...
s. An ISBN might be assigned for particular issues of a serial, in addition to the ISSN code for the serial as a whole. An ISSN, unlike the ISBN code, is an anonymous identifier associated with a serial title, containing no
information
Information is an Abstraction, abstract concept that refers to something which has the power Communication, to inform. At the most fundamental level, it pertains to the Interpretation (philosophy), interpretation (perhaps Interpretation (log ...
as to the
publisher
Publishing is the activities of making information, literature, music, software, and other content, physical or digital, available to the public for sale or free of charge. Traditionally, the term publishing refers to the creation and distribu ...
or its
location
In geography, location or place is used to denote a region (point, line, or area) on Earth's surface. The term ''location'' generally implies a higher degree of certainty than ''place'', the latter often indicating an entity with an ambiguous bou ...
. For this reason a new ISSN is assigned to a serial each time it undergoes a major title change.
Extensions
Since the ISSN applies to an entire serial, other identifiers have been built on top of it to allow references to specific volumes, articles, or other identifiable components (like the
table of contents
A table of contents (or simply contents, abbreviated as TOC), is a list usually part of the Book design#Front matter, front matter preceding the main text of a book or other written work containing the titles of the text's sections, sometimes with ...
): the
Publisher Item Identifier (PII) and the
Serial Item and Contribution Identifier
The Serial Item and Contribution Identifier (SICI) was a code (ANSI/ NISO standard Z39.56-1996 2002 used to uniquely identify specific volumes, articles or other identifiable parts of a serial. It was "intended primarily for use by those membe ...
(SICI).
Media versus content
Separate ISSNs are needed for serials in different media (except reproduction
microform
A microform is a scaled-down reproduction of a document, typically either photographic film or paper, made for the purposes of transmission, storage, reading, and printing. Microform images are commonly reduced to about 4% or of the original d ...
s). Thus, the
print and
electronic media
Electronic media are media that use electronics or electromechanical means for the audience to access the content. This is in contrast to static media (mainly print media), which today are most often created digitally, but do not require ele ...
versions of a serial need separate ISSNs, and
CD-ROM
A CD-ROM (, compact disc read-only memory) is a type of read-only memory consisting of a pre-pressed optical compact disc that contains computer data storage, data computers can read, but not write or erase. Some CDs, called enhanced CDs, hold b ...
versions and
web
Web most often refers to:
* Spider web, a silken structure created by the animal
* World Wide Web or the Web, an Internet-based hypertext system
Web, WEB, or the Web may also refer to:
Computing
* WEB, a literate programming system created by ...
versions require different ISSNs. However, the same ISSN can be used for different file formats (e.g.
PDF
Portable document format (PDF), standardized as ISO 32000, is a file format developed by Adobe Inc., Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, computer hardware, ...
and
HTML
Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...
) of the same online serial.
This "media-oriented identification" of serials made sense in the 1970s. In the 1990s and onward, with personal computers, better screens, and the Web, it makes sense to consider only ''content'', independent of media. This "content-oriented identification" of serials was a
repressed demand during a decade, but no ISSN update or initiative occurred. A natural extension for ISSN, the unique-identification of the articles in the serials, was the main demand application. An alternative serials' contents model arrived with the
indecs Content Model
indecs (an acronym of "interoperability of data in e-commerce systems"; written in lower case) was a project partly funded by the European Community ''Info 2000'' initiative and by several organisations representing the music, rights, text publi ...
and its application, the
digital object identifier
A digital object identifier (DOI) is a persistent identifier or handle used to uniquely identify various objects, standardized by the International Organization for Standardization (ISO). DOIs are an implementation of the Handle System; th ...
(DOI), an ISSN-independent initiative, consolidated in the 2000s.
Only later, in 2007, ISSN-L was defined in the new ISSN standard (ISO 3297:2007) as an "ISSN designated by the ISSN Network to enable collocation or versions of a continuing resource linking among the different media".
Use in URNs
An ISSN can be encoded as a
uniform resource name
A Uniform Resource Name (URN) is a Uniform Resource Identifier (URI) that uses the scheme. URNs are globally unique persistent identifiers assigned within defined namespaces so they will be available for a long period of time, even after the re ...
(URN) by prefixing it with "". For example,
''Rail'' could be referred to as "". URN namespaces are case-sensitive, and the ISSN namespace is all caps. If the checksum digit is "X" then it is always encoded in uppercase in a URN.
Problems
The URNs are
content-oriented, but ISSN is media-oriented:
* ISSN is not unique when the concept is "a journal is a set of contents, generally copyrighted content": the same journal (same contents and same copyrights) may have two or more ISSN codes. A URN needs to point to "unique content" (a "unique journal" as a "set of contents" reference).
:Example:
Nature
Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...
has an ISSN for print, 0028-0836, and another for the same content on the Web, 1476-4687; only the oldest (0028-0836) is used as a
unique identifier
A unique identifier (UID) is an identifier that is guaranteed to be unique among all identifiers used for those objects and for a specific purpose. The concept was formalized early in the development of computer science and information systems. ...
. As the ISSN is not unique, the
U.S. National Library of Medicine needed to create, prior to 2007, the NLM Unique ID (JID).
* ISSN does not offer
resolution mechanisms like a
digital object identifier
A digital object identifier (DOI) is a persistent identifier or handle used to uniquely identify various objects, standardized by the International Organization for Standardization (ISO). DOIs are an implementation of the Handle System; th ...
(DOI) or a URN does, so the DOI is used as a URN for articles, with (for historical reasons) no need for an ISSN's existence.
:Example: the DOI name "10.1038/nature13777" can be represented as an HTTP string by
''https://doi.org/''10.1038/nature13777
, and is
redirected (resolved) to the current article's page; but there is no ISSN online service, like
http://dx.issn.org/
, to resolve the ISSN of the journal (in this sample
1476-4687).
A unique URN for serials simplifies the search, recovery and delivery of data for various services including, in particular,
search systems and
knowledge databases.
ISSN-L (see
Linking ISSN above) was created to fill this gap.
Media category labels
The two standard categories of media in which serials are most available are ''print'' and ''electronic''. In
metadata
Metadata (or metainformation) is "data that provides information about other data", but not the content of the data itself, such as the text of a message or the image itself. There are many distinct types of metadata, including:
* Descriptive ...
contexts (e.g.,
JATS
The Jat people (, ), also spelt Jaat and Jatt, are a traditionally agricultural community in Northern India and Pakistan. Originally pastoralists in the lower Indus river-valley of Sindh, many Jats migrated north into the Punjab region in ...
), these may have standard labels.
Print ISSN
''p-ISSN'' is a standard label for "Print ISSN", the ISSN for the
print media
Mass media include the diverse arrays of media that reach a large audience via mass communication.
Broadcast media transmit information electronically via media such as films, radio, recorded music, or television. Digital media comprises b ...
(paper) version of a serial. Usually it is the "default media" and so the "default ISSN".
Electronic ISSN
''e-ISSN'' (or ''eISSN'') is a standard label for "Electronic ISSN", the ISSN for the
electronic media
Electronic media are media that use electronics or electromechanical means for the audience to access the content. This is in contrast to static media (mainly print media), which today are most often created digitally, but do not require ele ...
(online) version of a serial.
ROAD
* (est. 2013), produced by the
ISSN International Centre and
UNESCO
The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
See also
*
CODEN
CODEN – according to ASTM standard E250 – is a six-character, alphanumeric bibliographic code that provides concise, unique and unambiguous identification of the titles of periodicals and non-serial publications from all subject areas.
COD ...
*
WorldCat
WorldCat is a union catalog that itemizes the collections of tens of thousands of institutions (mostly libraries), in many countries, that are current or past members of the OCLC global cooperative. It is operated by OCLC, Inc. Many of the O ...
—an ISSN-resolve service
References
External links
ISSN International CentreISSN PortalList of 63800 ISSN numbers and titles*
* .
* .
* .
*
*
*
{{Use dmy dates, date=August 2017
Computer-related introductions in 1976
Checksum algorithms
ISO standards
Library science
Serial numbers
Unique identifiers