How to know how generous is the college for giving aid?

Answered

Need-based aid should actually be pretty easy to check—schools will usually say on their financial aid websites whether or not they meet "full financial need" or "100% of demonstrated need" or something along those lines. When you see that terminology, that means that those schools will offer you a package of grants, work-study, and federal loans that covers the gap between what you're able to pay (based on your family's income and savings) and the total cost of the school. If schools don't say that—basically if they don't guarantee to meet 100% or "full" need, then they're going to be significantly less generous in their offers.

For merit aid, it more depends on the applicant than the school, though private universities will typically give out much more merit aid than out-of-state public schools. The best gauge of what you might get in merit aid is how the chancing for a school shows up for you; if a school shows up as a safety, you're fairly likely to get some merit money from them, but if it shows up as a target or especially a reach, then you should assume that you likely will not receive any merit aid from them.