The cumulative GPA formula
New GPA = (current GPA × current credits + semester GPA × semester credits) ÷ total credits.
Example: a 3.4 GPA over 12 credits plus a 3.9 semester over 3 credits gives (40.8 + 11.7) ÷ 15 = 3.50.
To calculate everything from your individual grades instead, use the high school GPA calculator.