Impact Factor vs CiteScore — What's the Difference?
Two numbers dominate academic publishing decisions: the Journal Impact Factor (JCR, Clarivate) and CiteScore (Scopus, Elsevier). They sound interchangeable — both measure how often a journal's papers are cited. In practice they use different windows, different citation sources, and produce different numbers for the same journal. This page breaks down the mechanics so you can read either metric with confidence.
Side-by-Side Comparison (2026)
| Feature | Impact Factor (IF) | CiteScore |
|---|---|---|
| Provider | Clarivate (Web of Science) | Elsevier (Scopus) |
| Citation window | 2 years | 4 years |
| Formula (for year Y) | Citations in Y to papers published Y-1 & Y-2 ÷ papers published Y-1 & Y-2 | Citations in Y & 3 prior years to papers in those years ÷ papers in those years |
| Journal coverage | ~12,000 journals (JCR) | ~27,000 journals (Scopus) |
| Citable document types | Articles, reviews (curated list) | Articles, reviews, conference papers, data papers, short surveys |
| Update cadence | Annually, typically June | Annually in May/June; monthly CiteScore Tracker |
| Public access | Subscription (JCR via library) | Free on Scopus journal pages |
| Typical numeric range | 0 to ~100+ (extreme outliers) | Usually 10–30% higher than IF for the same journal |
How Each Metric is Calculated
Impact Factor (JCR)
The Impact Factor was created by Eugene Garfield in the 1960s and is published each June by Clarivate in the Journal Citation Reports. For a given year Y, it divides the number of citations received in Y to the journal's articles from the prior two years by the number of citable items the journal published in those two years.
Example: a journal's 2025 Impact Factor reflects citations received during 2025 to papers it published in 2023 and 2024, divided by the count of those papers.
CiteScore (Scopus)
CiteScore was introduced by Elsevier in 2016 and revised in 2020 to use a four-year window and more inclusive document types. For year Y, it divides the citations received during Y and the three prior years to papers published in that same four-year window by the number of those papers.
Example: a journal's 2025 CiteScore reflects citations received from 2022–2025 to papers published in 2022–2025. The four-year window is more forgiving of late-arriving citations.
Which One Should You Quote?
Quote Impact Factor when:
- Submitting to CV / promotion committees in biomedical or physical sciences — JCR is still the default.
- Your institution or funder explicitly requires a JCR-indexed journal (common in Asia and Eastern Europe).
- You want the most-recognized number in senior-level review panels.
Quote CiteScore when:
- The journal is in Scopus but not yet in JCR (common for new open access titles).
- You need a free, publicly-verifiable number readers can check without a subscription.
- Working in social sciences, humanities, or emerging interdisciplinary fields where Scopus coverage is broader.
Frequently Asked Questions
See Both Metrics on JournalsHub
JournalsHub tracks 821 journals with verified JCR Impact Factor data across our database of 1,483+ journals. Use the tools below to look up a specific journal or compare several side by side.
Related Reading
The Impact Factor and Journal Citation Reports are trademarks of Clarivate. CiteScore and Scopus are trademarks of Elsevier. JournalsHub is an independent aggregator and is not affiliated with either provider.