Last Updated on June 25, 2026 by Dr. Bhagat
The Journal Citation Reports (JCR) is a comprehensive journal evaluation tool produced by Clarivate Analytics as part of the Web of Science product family. JCR provides quantitative metrics—including the Impact Factor, immediacy index, and category rankings—to help researchers, librarians, and publishers evaluate and compare scholarly journals.
- JCR is produced by Clarivate Analytics as part of the Web of Science family
- The Impact Factor (IF) measures average citations per article over a 2-year window
- JCR 2025 covers 21,000+ journals across SCIE, SSCI, and ESCI
- Quartile rankings (Q1–Q4) compare journals within subject categories
- Access requires a subscription via institutions or libraries
OVERVIEW What Is Journal Citation Report?
Journal Citation Reports (JCR) is a database produced by Clarivate Analytics that provides information on the impact and influence of scholarly journals. It is a valuable tool for evaluating and comparing journals across various fields of research based on citation data from the Web of Science Core Collection.
JCR was originally published as the Science Citation Index by Eugene Garfield at the Institute for Scientific Information (ISI). Today, it is maintained by Clarivate Analytics, a Web of Science Group company.
METRICS Key Metrics in JCR
| Metric | Description |
|---|---|
| Impact Factor (IF) | Average number of citations received in a given year by articles published in the journal during the two preceding years. |
| 5-Year Impact Factor | Average citations over a 5-year window, providing a more stable metric for fields with slower citation patterns. |
| Immediacy Index | Average number of times an article is cited in the same year it is published, indicating how quickly research is picked up. |
| Eigenfactor Score | Measures total citation influence, weighted by the prestige of citing journals. |
| Article Influence Score | Average influence per article, similar to the Eigenfactor but normalized by number of articles. |
| Quartile (Q1–Q4) | Category-based ranking: Q1 = top 25%, Q2 = 25–50%, Q3 = 50–75%, Q4 = bottom 25%. |
FACTS Key Facts About Journal Citation Reports
- JCR was first published in 1975 by the Institute for Scientific Information (ISI)
- Clarivate acquired the Web of Science and JCR product lines in 2016
- JCR 2025 includes journals from SCIE, SSCI, and ESCI indexes
- Impact Factors are released annually in June
- Journals must complete a two-year citation window to receive their first IF
- Journals with excessive self-citation are flagged and may be excluded
- JCR data is used in tenure and promotion decisions at universities worldwide
ACCESS How to Access JCR
Journal Citation Reports is available through a subscription, typically provided by university libraries and research institutions. To access JCR:
- Visit https://jcr.clarivate.com
- Log in through your institutional credentials
- Search for a journal by title, ISSN, or publisher
- View Impact Factor, quartile ranking, and category data
COMPARISON What Is the Difference Between JCR and SJR?
| Feature | JCR (Clarivate) | SJR (SCImago) |
|---|---|---|
| Primary Metric | Impact Factor (IF) | SCImago Journal Rank (SJR) |
| Data Source | Web of Science | Scopus |
| Publisher | Clarivate Analytics | SCImago Lab / Elsevier |
| Coverage | 21,000+ journals | 30,000+ journals |
| Free Access | No (subscription) | Yes (scimagojr.com) |
| Update Frequency | Annual (June) | Annual |
METRICS EXPLAINED Impact Factor vs. Source Normalized Impact per Paper (SNIP)
The Impact Factor measures the average number of citations per article over a 2-year period. It is the most widely recognized journal-level metric but varies significantly across disciplines.
SNIP (Source Normalized Impact per Paper) is a metric from Scopus that corrects for differences in citation practices between fields. A SNIP of 1.0 means the journal’s citations are equal to the global average for its field; values above 1.0 indicate above-average citation impact.
METHODOLOGY How Is the Impact Factor Calculated?
The Impact Factor is calculated using the following formula:
÷
Total citable articles published in Years Y-1 and Y-2
For example, the JCR 2025 Impact Factor uses citations received in 2024 to articles published in 2022 and 2023, divided by the total number of citable articles (research articles and reviews) published in 2022 and 2023.
RANKINGS Top Journals by Impact Factor (JCR 2025)
| Rank | Journal | IF 2025 |
|---|---|---|
| 1 | Ca-A Cancer Journal for Clinicians | 286.13 |
| 2 | MMWR Recommendations and Reports | 196.50 |
| 3 | Nature Reviews Drug Discovery | 62.10 |
| 4 | New England Journal of Medicine | 56.70 |
| 5 | Nature Reviews Clinical Oncology | 45.40 |
| 6 | Nature Reviews Materials | 47.90 |
| 7 | Science | 41.85 |
| 8 | The Lancet | 80.30 |
| 9 | Cell | 64.50 |
| 10 | Nature | 50.50 |
FAQ Frequently Asked Questions
What is Journal Citation Report (JCR)?
JCR is a journal evaluation tool produced by Clarivate Analytics that provides Impact Factors and other citation metrics for scholarly journals indexed in Web of Science.
Who produces JCR?
Clarivate Analytics produces JCR as part of the Web of Science product family.
What is the Impact Factor?
The Impact Factor measures the average number of citations received in a given year by articles published in the journal during the two preceding years.
How often is JCR updated?
JCR is updated annually, with the new release typically published in June of each year.
Is JCR free to access?
No, JCR requires a subscription. However, many universities and libraries provide institutional access.
What is the difference between JCR and SJR?
JCR uses Web of Science data and publishes the Impact Factor. SJR uses Scopus data and publishes the SCImago Journal Rank. SJR is freely accessible.
What is SNIP?
SNIP (Source Normalized Impact per Paper) is a field-normalized metric from Scopus that adjusts for differences in citation practices across disciplines.
How is the Impact Factor calculated?
IF = (Citations in Year Y to articles from Years Y-1 and Y-2) ÷ (Total citable articles published in Years Y-1 and Y-2).
Are all journals given an Impact Factor?
Only journals indexed in Web of Science Core Collection (SCIE, SSCI, ESCI) that complete the required citation window receive an Impact Factor.
Can a journal lose its Impact Factor?
Yes, journals may be suppressed or excluded for excessive self-citation, citation stacking, or other forms of manipulation.
SOURCES References & Data Sources
- Journal Citation Reports – Clarivate Analytics. https://jcr.clarivate.com
- Web of Science – Clarivate. https://www.webofscience.com
- SCImago Journal Rank. https://www.scimagojr.com
- Scopus – Elsevier. https://www.scopus.com
RELATED Related Resources
- Clarivate JCR 2025 Impact Factors Release
- Journal Impact Factor Rankings 2025
- How to Check Journal Impact Factor
