In the 4.0 Grade Point Average system, a 3.3 GPA equals a ‘B’ letter grade. To find more grade equivalents, plug your numbers into the easy-to-use calculator found below. Determining your GPA depends on many factors. Most colleges look at class credits, time in class and individual grades. Read your school guidelines to learn more about how it works at your particular institution. Other possibilities include letter grades from A to F or percentages.