Publishing Metrics Update 2026

As a signatory to the San Francisco Declaration on Research Assessment (DORA), we suggest that no metric should be used in isolation to assess the value and impact of research. We present these metrics together to provide fuller context for each title.  

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Table of 2025 metrics for Access Microbiology 

Table of 2025 metrics for International Journal of Systematic and Evolutionary Microbiology 

Table of 2025 metrics for Journal of General Virology 

Table of 2025 for Journal of Medical Microbiology 

Table of 2025 metrics for Microbial Genomics 

Table of 2025 metrics for Microbiology 

For the text versions of the above tables, please visit our impact and metrics page. 

Definitions: 

• 2-year Journal Impact Factor: The Journal Impact Factor is defined as all citations to the journal in the current JCR year to items published in the previous two years, divided by the total number of scholarly items (these comprise articles, reviews, and proceedings papers) published in the journal in the previous two years. 

• 5-year Impact Factor: The 5-year journal Impact Factor is the average number of times articles from the journal published in the past five years have been cited in the JCR year. It is calculated by dividing the number of citations in the JCR year by the total number of articles published in the five previous years. 

• Immediacy Index: The Immediacy Index is the average number of times an article is cited in the year it is published. 

• Cited half-life: The median age of the articles that were cited in the JCR year. Half of a journal's cited articles were published more recently than the cited half-life. 

• CiteScore: CiteScore measures the average citations received per document published in the serial. 

• SNIP (Source Normalized Impact per Paper): The SNIP measures actual citations received relative to citations expected for the serial’s subject field. 

• Full-text downloads: How many times articles in that journal were accessed in 2024. 

• Altmetrics: Altmetrics are non-traditional metrics proposed as an alternative to citation impact metrics. A paper’s Altmetric score is a weighted measure of its mentions in the press and on social media, among others, and is displayed on each article page. This average shows the mean of every Altmetric score in that journal in the previous year.