Average GPA: 3.7. The average GPA at Trinity College is 3.7. This makes Trinity College Strongly Competitive for GPAs. (Most schools use a weighted GPA out of 4.0, though some report an unweighted GPA. This school did not officially report its average GPA, but we've estimated it here using data from over 1,000 schools.) With a GPA of 3.7, Trinity College requires you to be above average in your high school class. You'll need a mix of A's and B's, with a leaning toward A's. If you took some AP or IB classes, this will help boost your weighted GPA and show your ability to take college classes.