<p>Admissions offices’ policies vary as do they way they calculate GPA.
They often only use the core subjects: math, hard/lab sciences, english, foreign languages and history…leaving out things like pe, band, chorus, drivers ed, public speaking, that kind of thing.</p>
<p>It’s proprietary so you won’t know.</p>
<p>As for how a particular college calculates it for their matriculating students–that varies and you need to look it up on their web site.</p>
<p>Private schools using holistic admissions practices may not recalculate high school GPA; they may just look at courses and grades on the transcript to get an impression about what courses your selective (rigorous or not, or rigorous in particular subjects) and how well you did.</p>