Journal Impact Factor: What It Means and How to Check It
Meet the Expert
Shruti Sharma
Academic Writing Coach & Research Communication Specialist
- Expert in journal metrics including Impact Factor, CiteScore, SJR, and h-index
- Guided 200+ researchers in selecting high-impact journals aligned with their research area
- Experienced in helping institutions build research portfolios in Q1 and Q2 journals
The Journal Impact Factor (JIF) is an annual metric published by Clarivate that reflects the average number of citations received by articles published in a journal during the preceding two years. It is the most cited journal-level metric worldwide and is used by researchers, institutions, and funding bodies to assess journal prestige — though it has known limitations.
How Is Journal Impact Factor Calculated?
The formula for Impact Factor is straightforward:
Impact Factor (Year X) = Citations in Year X to articles published in Years X-1 and X-2 ÷ Total citable articles published in Years X-1 and X-2
For example, if a journal published 100 articles in 2023 and 2024, and those articles received 450 citations in 2025, the 2025 Impact Factor would be 450 ÷ 100 = 4.50.
Journal Impact Factor Ranges by Field
What Is a Good Impact Factor? Field-by-Field Comparison
Top journals: IF 20–100+; Average Q1: 5–15; Good target: 3+
Top journals: IF 5–20; Average Q1: 3–8; Good target: 2+
Top journals: IF 10–60; Average Q1: 4–10; Good target: 3+
Top journals: IF 3–10; Average Q1: 2–5; Good target: 1.5+
Top journals: IF 1–4; Average Q1: 0.8–2; Good target: 0.8+
Many top journals lack JIF; use ERIH PLUS or AHCI for ranking
Impact Factor vs CiteScore vs SJR: Key Differences
| Metric | Published By | Database | Citation Window | Coverage |
|---|---|---|---|---|
| Journal Impact Factor (JIF) | Clarivate | Web of Science | 2 years | ~21,000 journals |
| CiteScore | Elsevier/Scopus | Scopus | 4 years | ~27,000+ journals |
| SJR (Scimago Journal Rank) | Scimago Lab | Scopus | 3 years | ~27,000+ journals |
| SNIP | CWTS / Elsevier | Scopus | 3 years | ~27,000+ journals |
| h-index (journal level) | Various | Multiple | All years | Varies by source |
How to Check a Journal's Official Impact Factor
There is only one authoritative source for the official Journal Impact Factor: Clarivate's Journal Citation Reports (JCR). Many other websites claim to list impact factors — treat them as unreliable unless they are sourcing from JCR directly.
| Platform | URL | Metric Available | Access |
|---|---|---|---|
| Journal Citation Reports (JCR) | jcr.clarivate.com | Official JIF (most authoritative) | Institutional subscription (many universities have access) |
| Scopus Journal Metrics | scopus.com/sources | CiteScore, SJR, SNIP | Free |
| Scimago Journal Rank | sjr.scimagojr.com | SJR, H-index, quartile | Free |
| Scopus Source List | Elsevier website (Excel download) | CiteScore, quartile, ISSN | Free download |
Fake Impact Factors: How to Spot Them
Many predatory journals list an "impact factor" from organisations like Global Impact Factor (GIF), Universal Impact Factor (UIF), or Index Copernicus Value (ICV). These are not recognised by any legitimate academic body. The only official Impact Factor is published by Clarivate in JCR. If a journal's impact factor is not verifiable in JCR, it is either a non-WoS journal (check CiteScore instead) or using a fraudulent metric.
Limitations of the Journal Impact Factor
- JIF measures journal-level citations, not the quality of individual articles — a paper in a high-IF journal may be less cited than a paper in a low-IF journal
- Fields with high citation cultures (medicine, biology) naturally produce higher IFs — direct cross-field comparison is misleading
- JIF can be manipulated by editorial practices (e.g., publishing more review articles, which receive more citations)
- The 2-year window disadvantages fields where citation impact peaks after 5+ years (e.g., mathematics, physics)
- The San Francisco Declaration on Research Assessment (DORA) recommends against using JIF as the primary measure of research quality
Need help selecting the right journal with the appropriate impact factor for your research? Thesis Ace Writers' journal selection experts match your paper to the best-fit indexed journal.
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Frequently Asked Questions
Click a question to expand the answer.
The Journal Impact Factor (JIF) is a metric published annually by Clarivate (via the Journal Citation Reports) that measures the average number of citations received per article published in a journal over the previous two years. It is the most widely used journal-level metric in academic publishing, though it has limitations and should not be used as the sole measure of research quality.
The official Journal Impact Factor is calculated exclusively by Clarivate and published in the Journal Citation Reports (JCR). Only journals indexed in Web of Science (SCIE or SSCI) have an official JIF. Any journal claiming an impact factor from other organisations (like Global Impact Factor, Universal Impact Factor, etc.) is using an unofficial and unreliable metric — a common tactic of predatory journals.
What constitutes a 'good' impact factor varies significantly by field. In high-citation fields like molecular biology or medicine, top journals have IFs of 10–50+. In mathematics or humanities, a journal with an IF of 1–2 may be top-ranked in its field. The best approach is to compare journals within the same subject category and quartile (Q1, Q2) rather than using absolute IF values.
Impact Factor (JIF) is published by Clarivate and covers journals in Web of Science, using a 2-year citation window. CiteScore is published by Elsevier/Scopus and covers a broader set of journals using a 4-year citation window, which tends to produce higher numerical scores. Both are legitimate journal-level metrics. CiteScore covers more journals (including those not in Web of Science), making it useful for Scopus-indexed journals without a JIF.
Yes, if a journal is indexed in both Scopus and Web of Science (SCIE/SSCI), it will have both a CiteScore (from Scopus) and a Journal Impact Factor (from Clarivate/JCR). However, many journals are indexed in Scopus but not in Web of Science, in which case they will have a CiteScore and SJR (from Scimago) but no official JIF.