On October 28, 2021 (JST), Times Higher Education (THE) announced the "THE World Reputation Rankings 2021." Following last year's results, Keio University was ranked in the top 151-175 universities in the world, 8th among Japanese universities, and tied with Waseda University as the top private university in Japan.
Rankings of the top 200 universities in the world are decided based on responses of researchers around the world about the reputation of universities for their research and educational capacities. The current ranking is based on a total of 10,963 responses obtained from researchers in 128 countries from a survey conducted between November 2020 and February 2021. The only Japanese universities that made the list were the 11 research universities that are also members of RU11 (a consortium of top Research Universities in Japan), such as Keio University.
For further details, refer to the following link.
https://www.timeshighereducation.com/world-university-rankings/2021/reputation-ranking