To check whether a journal is indexed in Web of Science, search its title or ISSN in Clarivate’s free Master Journal List at mjl.clarivate.com. If the journal appears, its profile page lists which Core Collection indexes it belongs to — SCIE, SSCI, AHCI, or ESCI. If it does not appear in the Master Journal List, it is not currently indexed in the Core Collection.
The Web of Science Master Journal List (MJL) is Clarivate’s free, public lookup tool for one specific question: is this journal currently indexed in the Web of Science Core Collection, and if so, in which index? It is not the same thing as “Web of Science” the broader research platform, and treating the two as interchangeable is where most confusion about a journal’s indexing status starts. This guide covers what MJL actually is, how it differs from being “in Web of Science” in the loose, general sense, how to search it, what a journal profile page shows, and how the four Core Collection indexes it covers relate to each other.
For how to search Web of Science’s literature database itself (finding articles, not checking journal status), see CASRAI’s How to Search Web of Science Effectively. For the broader question of what “indexed” means across databases generally, see What Does It Mean for a Journal to Be Indexed?. This page narrows in on the Master Journal List specifically, as its own tool with its own scope and mechanics.
What the Master Journal List Actually Is
MJL is Clarivate’s public directory of every journal, book series, and conference proceedings title currently or formerly covered by the Web of Science Core Collection. It is accessible free at mjl.clarivate.com without a Web of Science subscription, which makes it the standard first stop for an author, editor, or research administrator who needs to answer “is this specific journal indexed?” without needing library-mediated database access.
This distinction matters operationally: a researcher’s institution may not carry a Web of Science subscription, or a journal may be marketing itself as “indexed in Web of Science” without specifying where. MJL settles the question directly against Clarivate’s own authoritative list rather than trusting a journal’s own claim.
MJL vs. “Being in Web of Science”: Why the Distinction Matters
“Web of Science” is used loosely to mean several different things, and MJL only covers one of them. The Web of Science platform itself is broader than the Core Collection: beyond the six citation indexes bundled into the Core Collection, Clarivate also makes specialty databases available on the same platform (for example, subject-specific tools covering biological or chemical literature), and access to those varies by institutional subscription. The Master Journal List covers Core Collection titles specifically — it is not a comprehensive index of everything searchable somewhere on the Web of Science platform.
Two practical consequences follow:
- A journal not found in MJL is not Core Collection-indexed, regardless of what else might be true about its visibility on the broader platform or in a specialty database.
- Being found in MJL is not one uniform status. MJL tells you which index a title sits in (Science Citation Index Expanded, Social Sciences Citation Index, Arts & Humanities Citation Index, or Emerging Sources Citation Index), and that distinction carries real weight — see the index-by-index section below.
How to Search the Master Journal List
MJL supports lookup by journal title, keyword, or ISSN/eISSN. Searching by ISSN is the most precise method when a title has changed names, has a close near-duplicate title in another field, or when you want to confirm you have the correct edition (print vs. electronic ISSN) of a journal that publishes in both formats.
A search returns a list of matching titles; selecting one opens a journal profile page with more detail than the search-results list alone shows.
What a Journal Profile Page Shows
A journal’s MJL profile page is the authoritative record of its Core Collection status. It typically includes:
- ISSN and eISSN — useful for confirming you have matched the correct title when a publisher runs both print and electronic editions under related-but-distinct identifiers.
- Publisher name and location.
- Which Web of Science Core Collection index (or indexes) the title is covered in — SCIE, SSCI, AHCI, and/or ESCI.
- Coverage details, including the subject categories the journal is classified under within Web of Science.
- Journal-level indicators where applicable, such as whether the title currently receives a Journal Impact Factor through Journal Citation Reports (JCR).
A downloadable master list (exportable to spreadsheet format) is also available for bulk lookups — useful for a research office or library checking indexing status across many titles at once rather than one at a time through the search interface.
The Four Core Collection Indexes MJL Covers
MJL will place an indexed title into one or more of the following, and the difference between them matters for how much weight the indexing status should carry:
- Science Citation Index Expanded (SCIE) — the core science and technology index, covering thousands of actively publishing journals across science subject categories, with full editorial vetting against Clarivate’s quality and impact criteria.
- Social Sciences Citation Index (SSCI) — the equivalent index for social-science titles, evaluated and maintained separately from SCIE; acceptance into one does not extend to the other, since each is reviewed against its own discipline-specific quality bar.
- Arts & Humanities Citation Index (AHCI) — the equivalent index for arts and humanities titles.
- Emerging Sources Citation Index (ESCI) — covers journals under evaluation that have not yet met the full SCIE, SSCI, or AHCI selection criteria. ESCI is still part of the Web of Science Core Collection and is searchable in MJL and on the platform, but it is a distinct, lower editorial bar than full SCIE/SSCI/AHCI inclusion — a title can sit in ESCI for years without ever being promoted, or can be promoted or delisted after re-evaluation. Since the 2023 Journal Citation Reports release, ESCI titles became eligible to receive a Journal Impact Factor alongside SCIE/SSCI/AHCI titles (before that release, JIF eligibility was limited to SCIE and SSCI only) — but ESCI status itself is still a materially different, less selective signal than full-index inclusion, and it is worth checking which specific index a title sits in rather than treating “in Web of Science” as one undifferentiated status.
For what the Journal Impact Factor is and how it is calculated once a title is JCR-eligible, see CASRAI’s Journal Impact Factor and Quartile Rankings guide.
How Journals Get Added or Removed from Coverage
Inclusion in the Web of Science Core Collection is an editorial decision made by Clarivate’s Web of Science editors, not an automatic or purchasable status. Clarivate publishes evaluation criteria covering journal quality, editorial rigor, publishing ethics, and regularity of publication; editors retain discretion in applying them to both new-title submissions and periodic re-evaluation of already-indexed titles. A title can be removed from coverage if it stops meeting quality standards, fails to comply with publication-ethics expectations, or is found to have violated Clarivate’s editorial policies — delisting does happen, and a formerly-indexed title that no longer appears (or appears with a coverage end date) in MJL is a meaningful signal in its own right, not a database glitch.
Because criteria and coverage change over time, MJL — not a journal’s own website, a cached search result, or a prior year’s records — is the source to check for current status.
Why This Matters for Research Administrators and Authors
Journal indexing status in Web of Science routinely feeds into decisions well beyond literature searching: some tenure and promotion committees and some funders treat Core Collection inclusion (and, more specifically, which index a title sits in) as one input among several when evaluating a researcher’s publication record, and it is a standard field in publisher-vetting checklists used to screen for predatory or low-quality venues. Because a claim of “indexed in Web of Science” is easy to make and hard to verify from a journal’s own marketing, confirming the claim directly in MJL — and noting whether the title sits in SCIE/SSCI/AHCI versus ESCI — is the reliable way to check it rather than take it at face value.
Frequently Asked Questions
Is the Web of Science Master Journal List free to use?
Yes. MJL is publicly accessible at mjl.clarivate.com without a Web of Science subscription. This is distinct from the Web of Science platform itself and from Journal Citation Reports, both of which are typically subscription-gated at research libraries.
How do I check if a specific journal is indexed in Web of Science?
Search the journal’s title or ISSN directly in MJL at mjl.clarivate.com. If it appears, its profile page will show which Core Collection index (or indexes) it is covered in. If it does not appear, it is not currently part of the Web of Science Core Collection, regardless of what the journal’s own website claims.
What is the difference between the Master Journal List and Web of Science Core Collection?
The Core Collection is the set of citation indexes (SCIE, SSCI, AHCI, ESCI, plus the Conference Proceedings and Book Citation Indexes) that Clarivate curates and makes searchable on the Web of Science platform. MJL is the free public directory tool for checking which journals are covered by those indexes — it is a lookup tool for the Core Collection’s contents, not a separate database.
Does being in the Emerging Sources Citation Index (ESCI) count as “being in Web of Science”?
Yes, in the sense that ESCI is part of the Web of Science Core Collection and ESCI titles are searchable in MJL and on the platform. But ESCI is a distinct, less selective tier than SCIE, SSCI, or AHCI — it covers journals under evaluation that have not yet met those indexes’ full criteria — so it is worth specifying which index a title sits in rather than treating all Core Collection inclusion as equivalent.
How often is the Master Journal List updated?
Clarivate adds and removes titles from Core Collection coverage on an ongoing basis as new journals are evaluated and existing titles are re-reviewed, so MJL reflects current status rather than a fixed annual snapshot. Because coverage changes, a specific journal’s status should be re-checked directly in MJL rather than assumed to be static from a prior lookup.
