An ISSN (International Standard Serial Number) is an eight-digit standard identifier for serials such as journals. It is usually written like 1234-5678 and may end with X as a check character. Print ISSN and electronic ISSN (e-ISSN) often differ. Two ISSNs for one journal are not an error—they mark formats. A DOI identifies an article object; an ISSN identifies the serial.
Index applications, library records, and metric matching run on ISSNs. Fake or mangled ISSNs appear on predatory sites—verify via the official ISSN portal or national centre. JCR/Scopus matching also leans on ISSN; hyphenated vs unhyphenated forms can break searches—normalize them.
This site’s Find quartile tool and journal catalog support ISSN search with or without hyphens. Putting an ISSN next to the journal title in a dossier disambiguates same-name titles. ISBN is for books—do not confuse it with ISSN.
For editors, obtaining an ISSN is a basic launch step, but an ISSN alone is not a quality or indexing guarantee. The indexing and predatory-journals entries stress that limit. Title changes can affect ISSN policy—check historical records.
When you use ISSN in a dossier or journal choice, state the year, official source, and category or collection name when relevant. Cross-reading related entries in this glossary prevents slogan-only explanations and produces verifiable wording that matches how committees and funders actually read evidence.