U.S. ISSN Center, Library of Congress
International Standard Serial Number (ISSN)

ISSN for Electronic Serials

ISSN are appropriate for serials in any medium, including electronic serials. A separate ISSN is required for each medium. To date, thousands of ISSN have been assigned to serials on computer disk, CD-ROM and online electronic serials.

Criteria for Assigning ISSN

The criteria for determining if a serial qualifies for an ISSN applies equally to electronic and print publications: an intention to continue publishing indefinitely and being issued in designated parts. In the case of electronic serials--especially those available online, such as on the Internet--the most significant criterion is that the publication is divided into parts or issues which carry unique, numerical designations by which the individual issues may be identified, checked in, etc. Electronic serials that are issued as individual articles also meet this criterion as long as the articles carry a unique designation. Thus, a database issued quarterly on CD-ROM and carrying quarterly date designations would be eligible for an ISSN while the same database as an online service which was being continually and seamlessly updated would not be eligible.

How Many ISSN?

Another question that arises with serials in electronic form is how many ISSN are needed. Separate ISSN are needed for serials in different media (with the exception of reproduction microforms). Thus the print and electronic versions of a serial need separate ISSN. Also, a CD-ROM version and an online version of a serial require different ISSN since two different media are involved. However, the same ISSN can be used for different file formats (ASCII, PostScript, and hypertext) of the same online serial. Please indicate all the different versions available in the appropriate place on the ISSN application form or in the "other information" block of the form. You may wish to download and save a copy of the form if you have many publications.

How to Apply

Use the ISSN application form for computer disk, CD-ROM and online serials, both pre- and post publication.. Prepublication requests are encouraged so the ISSN can appear on the publication from the first issue forward. Prepublication requests should be accompanied by some form of mock-up. This could consist of draft screen prints of the following screens, e-mailed drafts of the screens in question or, for online serials, instructions on how we can access these screens online:

  1. Title screen
  2. Screen that includes the serial's numeric or chronologic designation (date or issue number).
  3. Any screens that give general information about how to subscribe, frequency, publisher, copyright, etc.

Completing the Application Form

The application form may be completed online and then printed and mailed. Most of the form is self-explanatory but questions sometimes arise about the following:

Printing the ISSN

For serials that have any kind of physical medium, such as CD-ROMs or floppy disks, the ISSN should be printed both on the disk label and on the title screen of the publication itself. If there is no title screen, the ISSN should be printed in the location where publisher and copyright information are given.

For serials available only in online versions, the ISSN should appear on the title screen or home page and/or in the masthead or other areas where information about publisher, frequency, subscribing, copyright, etc. is given.

If multiple ISSN have been assigned because the serial is available in multiple media, all of the ISSN should be printed on each version, e.g. ISSN 1234-567X (Print), ISSN 7654-3210 (Online).

After Publication

In order to complete the registration for an ISSN issued prior to publication, you MUST send our office the first issue or its equivalent. For serials on diskettes or CD-ROM, we prefer that you send us the actual publication. Additionally, (or alternatively if it is not feasible to send the actual publication) please send us a screen print of the title screen or other screens that include publication information so that we can update your record even if we do not have the appropriate hardware or software to view it. For serials transmitted online, please provide us with a URL, password (if necessary), and any other instructions needed to access the publication online so that we may complete your registration based on information from the published serial.

For further information, contact:

Library of Congress
ISSN Publisher Liaison Section
101 Independence Avenue, S.E.
Washington, D.C. 20540-4284
(202) 707-6452 (voice)
(202) 707-6333 (fax)
issn@loc.gov (e-mail)


Regina Reynolds,
Coordinator, U.S. ISSN Center
Library of Congress
(202) 707-6379 (voice)
(202) 707-6333 (fax)
rrey@loc.gov (e-mail)

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 Library of Congress
Library of Congress Help Desk ( October 24, 2008 )