CWTS Leiden Ranking

The CWTS Leiden Ranking is an annual global university ranking based exclusively on bibliometric indicators. The rankings are compiled by the Centre for Science and Technology Studies (Dutch: Centrum voor Wetenschap en Technologische Studies, CWTS) at Leiden University in the Netherlands. The Clarivate Analytics bibliographic database Web of Science is used as the source of the publication and citation data.

The Leiden Ranking ranks universities worldwide by number of academic publications according to the volume and citation impact of the publications at those institutions. The rankings take into account differences in language, discipline and institutional size. Multiple ranking lists are released according to various bibliometric normalization and impact indicators, including the number of publications, citations per publication, and field-normalized impact per publication. In addition to citation impact, the Leiden Ranking also ranks universities by scientific collaboration, including collaboration with other institutions and collaboration with an industry partner.

The first edition of the Leiden Ranking was produced in 2007. The 2014 rankings include 750 universities worldwide, which were selected based on the number of articles and reviews published by authors affiliated with those institutions in 2009–2012 in so-called "core" journals, a set of English-language journals with international scope and a "sufficiently large" number of references in the Web of Science database.

According to the Netherlands Centre for Science and Technology Studies, the crown indicator is Indicator 4 (PP top 10%), and is the only one presented in university rankings by the Swiss State Secretariat for Education, Research and Innovation website (UniversityRankings.ch).