FWIW: When you apply to college, your high school sends their “profile” to an Admissions Office which allows a college to “decode” a student’s GPA, regardless if it’s weighted or unweighted. Many high schools have their profiles on-line for any college to see. If you haven’t seen your high school’s profile, ask your GC for a copy. For example, here is a college profile which displays weighted GPA. Notice the number of students at the very top end of the weighted GPA – if you are NOT in that top end (16 students), or in the second to top end (42 students), you should not be applying to Harvard from this high school, as you are probably not a competitive applicant in relation to your peers from this high school: http://www.bls.org/ourpages/auto/2013/5/24/55204166/2015-16%20BLS%20Profile.pdf