Most selective universities in the US?

I'm a high school junior starting my college search, and I'm curious about which universities in the US are considered the toughest to get into. Any insights on acceptance rates or reputation would be helpful.

There are several universities in the United States that are known to be highly selective due to their low acceptance rates. Here is a brief list of some of these institutions:

1. Stanford University: With an acceptance rate of around 4%, Stanford is one of the most selective institutions in the country. It's known for its strong engineering and tech-related programs, thanks to its proximity to Silicon Valley.

2. Harvard University: Its acceptance rate is around 5%. Besides its reputation for academic excellence, Harvard's social sciences, biological sciences, and humanities departments are particularly strong.

3. Columbia University: Columbia accepts around 6.2% of applicants. It's recognized for its strong programs in Social Science, Engineering, and Biomedical Sciences, among others.

4. Princeton University: This Ivy League school, known for its strong programs in Social Science, Engineering, and Biological Sciences, also has an acceptance rate near 5.5%.

5. California Institute of Technology (Caltech): Though Caltech is a smaller institution, it's extremely competitive with an acceptance rate of around 7%. It's known for its science, technology, engineering, and mathematics programs.

6. Massachusetts Institute of Technology (MIT): MIT also has an acceptance rate of around 7%, and it's particularly renowned for its math, science, and engineering programs.

Remember, the acceptance rate is not the only metric for gauging a college's selectivity. Other factors such as the Academic Index, which represents the strength of the applicant's grades and test scores, are also taken into account during the admissions process. As always, finding a good fit for you based on your interests, values, and career goals is just as important as considering a school's selectivity.