The ranking of universities can vary depending on the criteria and organization conducting the assessment. However, according to widely recognized global university rankings such as the QS World University Rankings and the Times Higher Education (THE) World University Rankings, the Massachusetts Institute of Technology (MIT) in the United States is frequently ranked as the number one university in the world.
Keep in mind that the "best" university can also depend on your field of study, personal goals, and other factors such as campus culture, location, and available resources.