Journal Impact Factor Calculator: 2-Year and 5-Year JIF, Self-Citations, Immediacy and CiteScore

How it works

JIF (year Y) = citations in Y to items from Y−1 and Y−2 ÷ citable items published in Y−1 and Y−2 · 5-year JIF uses items from Y−1 to Y−5 · JIF without self-citations removes the journal’s citations to itself from the numerator · Immediacy index = citations in Y to items from Y ÷ items from Y · CiteScore = citations in Y−3…Y to documents from Y−3…Y ÷ those documents · Quartile from rank ÷ category size (Q1 ≤ 0.25); JIF percentile = (N − rank + 0.5) ÷ N × 100

The Journal Impact Factor, published each June in Clarivate’s Journal Citation Reports (JCR), is a journal-level average. Take the citations a journal received in one year to everything it published in the two previous years, and divide by the number of citable items (articles and reviews) it published in those two years. Citations to editorials, letters and news still count in the numerator even though those items are left out of the denominator. The five-year JIF does the same over five years and suits fields where citations build slowly. The JIF without self-citations shows how much of the score comes from the journal citing itself. The immediacy index measures how fast papers are picked up in their own year. Scopus’s CiteScore uses a four-year window: citations received over four years to articles, reviews, conference papers, book chapters and data papers from the same four years, divided by the number of those documents. Since that method arrived in 2020 its values usually run higher than the JIF. Citation density varies hugely between fields, so a JIF of 2 can be top-quartile in mathematics and bottom-quartile in cell biology. That is why JCR ranks journals within categories: the quartile comes from rank ÷ number of journals, and the JIF percentile is (N − rank + 0.5) ÷ N. Treat the rough field context as a guide only.

Worked example

A journal received 1,840 citations in 2025 to its 410 citable items from 2024 and 2,210 to its 395 items from 2023. 2025 JIF = 4,050 ÷ 805 = 5.031, shown in JCR as 5.0. Without the 320 self-citations (7.9% of the total) it is 3,730 ÷ 805 = 4.634. Adding 4,100 citations to 1,150 items from 2020–2022 gives a five-year JIF of 8,150 ÷ 1,955 = 4.169. The immediacy index is 210 ÷ 400 = 0.525, and the CiteScore is 12,800 ÷ 1,620 = 7.9.

Sources: Wikipedia: Impact factor (calculation, citable items, 5-year JIF, immediacy index, DORA) · Wikipedia: CiteScore (four-year method since 2020, document types) · Elsevier: CiteScore metrics

Frequently asked questions