Journal Citation Reports (JCR)

What a Journal Citation Reports release actually contains

Journal Citation Reports (JCR) is not a single number — it is an annual, multi-metric report covering tens of thousands of journals. Each year’s release (e.g. “JCR 2026,” published June 2026 using 2025 citation data) gives every eligible journal its own JCR Profile page carrying several distinct, independently calculated indicators, not just the Journal Impact Factor:

• Journal Impact Factor (JIF) — citations in year Y to a journal’s citable items from years Y-1 and Y-2, divided by the count of those citable items. The metric most people mean when they say “impact factor.”
• JIF 5-Year — the same calculation extended to a five-year citation window, which smooths out year-to-year volatility for journals with slower citation uptake.
• Journal Citation Indicator (JCI) — introduced in the 2021 release. A field-normalized score (category average = 1.0) built so that journals in different subject categories — a chemistry journal and a history journal, for instance — can be compared on a common, discipline-adjusted scale in a way raw JIF cannot support.
• Eigenfactor Score and Article Influence Score — an eigenvector-style (“PageRank”-like) weighting of five years of citations that accounts for the prestige of the citing journal, not just the raw citation count, licensed by Clarivate from the University of Washington’s Eigenfactor project.
• Immediacy Index — how quickly a journal’s articles get cited in their year of publication, a proxy for how fast-moving a field or journal is.
• Quartile ranking (Q1–Q4) — a journal’s rank position within its assigned JCR subject category, expressed as a quartile of that category’s full ranked list.
• Supporting descriptive data — total citations, cited/citing half-life, percentage of open-access articles, and category rank tables.

Confusing any one of these for “the JCR number” is a common source of miscommunication — a journal’s JIF, JCI, and quartile position can each tell a different story about the same journal in the same release year.

How quartile rankings are actually calculated

A journal’s Q1–Q4 quartile is determined by sorting every journal in its assigned JCR subject category by a ranking metric, then dividing that ranked list into four equal segments. Landing in Q1 means the journal outranks at least 75% of journals in its category for that metric and that release year. Two details matter in practice: a journal can be classified into more than one JCR category (common in interdisciplinary fields) and will carry a separate quartile per category, and — following a 2024 methodology change — arts and humanities categories are ranked by JCI rather than JIF, since Clarivate determined JCI’s field-normalization better suits how citation practices work in those disciplines. See CASRAI’s companion guide, Journal Impact Factor and Quartile Rankings, for a full worked walkthrough of finding and interpreting a specific journal’s quartile.

Which journals are eligible

JCR metrics are built from citation data captured across Clarivate’s Web of Science Core Collection indices — chiefly the Science Citation Index Expanded (SCIE), the Social Sciences Citation Index (SSCI), the Arts & Humanities Citation Index (AHCI), and the Emerging Sources Citation Index (ESCI). This eligibility list is more current than it might appear from older guidance: through 2022, only SCIE- and SSCI-indexed journals received a Journal Impact Factor. Starting with the 2023 JCR release, Clarivate extended JIF eligibility to all Web of Science Core Collection journals meeting its quality criteria, including AHCI and ESCI titles — over 9,000 journals received a JIF for the first time that year. A journal’s presence in Web of Science does not automatically mean a JCR profile exists for it: coverage still depends on which Core Collection index accepted it, and JCR builds its report only from that citation data, not from Web of Science search results directly.

Who publishes it, and history

JCR was created by Eugene Garfield and Irving H. Sher at the Institute for Scientific Information (ISI), with the first edition published in 1975 using 1974 citation data — the origin of the Journal Impact Factor itself. Ownership of ISI, and with it JCR, passed through the Thomson Corporation (1992), Thomson Reuters (formed 2008), and finally Clarivate (spun out and rebranded in 2016), which is the current publisher. The report moved from print to electronic distribution over the following decades and is now published as an online platform (jcr.clarivate.com), with JCI added in 2021 and the JIF-eligibility expansion to AHCI/ESCI journals landing in 2023, as described above. The 2026 release (published June 2026) covers 22,643 journals across 254 subject categories from 113 countries.

How JCR is accessed

JCR is a Clarivate subscription product — there is no free, complete way to browse the full official dataset. Most research university libraries carry access, commonly bundled with a Web of Science subscription, since the two products share the same underlying citation data. A library’s database list or a subject librarian is the fastest way to confirm access; a journal’s own website often states its current JIF or quartile directly, though that self-reported figure should still be treated as a claim to verify against the actual JCR profile page where citation-integrity questions matter (a scenario CASRAI’s guide on looking up a journal’s current Impact Factor covers in more depth). Confirming whether a journal is indexed at all — a prerequisite for it having any JCR metrics — is free via the Web of Science Master Journal List.

JCR is not the same product as these adjacent things

• Web of Science — the citation-indexing and discovery platform JCR draws its data from. Searching or browsing Web of Science is not the same as accessing a JCR report, even where both are bundled in the same library subscription.
• SCIE / SSCI / AHCI / ESCI — the individual citation indexes within Web of Science’s Core Collection. A journal’s index membership determines its JCR eligibility, but the index itself is not JCR.
• The Journal Impact Factor — one metric reported inside JCR, not the report itself. “JCR” and “impact factor” get used interchangeably in casual conversation, but a JCR release also reports JCI, Eigenfactor, Article Influence, and quartile data that JIF alone does not capture.
• Scopus and its metrics (CiteScore, SCImago Journal Rank) — a wholly separate Elsevier product built on a different underlying citation database, with its own selection criteria and formulas. A journal’s Scopus-derived metrics and its Clarivate/JCR metrics will generally differ and are not interchangeable, even when both get informally called “the impact factor.” See CASRAI’s Scopus vs Web of Science vs OpenAlex comparison for the underlying database differences.

Responsible use

JCR itself documents responsible-use guidance for its own metrics, and the broader research-assessment reform movement — the San Francisco Declaration on Research Assessment (DORA) and the Coalition for Advancing Research Assessment (CoARA) — specifically targets the practice of treating any single JCR-reported figure as a proxy for individual-article or individual-researcher quality; see CASRAI’s responsible metrics entry and the DORA and CoARA comparison guide. This page is about what JCR is and contains, not a re-litigation of that debate; see CASRAI’s Journal Impact Factor and Quartile Rankings guide for that fuller treatment.