I know grades aren't everything to get into a PhD program, but do know it plays a significant part in determining how well one will do in graduate school. With that being said, what does it take to get accepted into a top 20 math or physics PhD program? I've seen some applicant profiles online and their GPAs seem to be around 3.8 or higher, with stellar GRE scores. Is this because many international students apply for these PhD programs and they need higher grades? How will I stand out among these applicants? I predict my GPA to be around 3.5-3.6 by the end of freshman year, but I will have only taken three quarters of the calculus series, an introductory computer science class (python), and general education classes. I know the classes are going to start to get very very difficult, and I'm afraid my GPA will plummet. At what point do you think I should stop thinking about applying to a PhD program right after undergrad, and maybe attend a masters program? Thank you.