How to Calculate GPA: Formula, Letter Grades & Weighted GPA
GPA (Grade Point Average) is the standard measure of academic performance at most US schools and universities. This guide covers exactly how it's calculated — including weighted GPA for honours and AP classes.
The Basic GPA Scale
Most US schools use a 4.0 scale:
| Letter Grade | Percentage | Grade Points | |-------------|------------|--------------| | A+ | 97–100% | 4.0 | | A | 93–96% | 4.0 | | A− | 90–92% | 3.7 | | B+ | 87–89% | 3.3 | | B | 83–86% | 3.0 | | B− | 80–82% | 2.7 | | C+ | 77–79% | 2.3 | | C | 73–76% | 2.0 | | C− | 70–72% | 1.7 | | D+ | 67–69% | 1.3 | | D | 63–66% | 1.0 | | D− | 60–62% | 0.7 | | F | Below 60%| 0.0 |
Note: Some schools don't use plus/minus grades — they only have A, B, C, D, F at 4.0, 3.0, 2.0, 1.0, and 0.0.
How to Calculate Unweighted GPA
Step 1: Convert each grade to grade points using the table above.
Step 2: Multiply each grade point value by the number of credit hours for that course.
Step 3: Sum all the quality points (grade points × credit hours).
Step 4: Divide by the total credit hours.
GPA = (Σ(Grade Points × Credit Hours)) / (ΣCredit Hours)
Worked Example
| Course | Grade | Grade Points | Credits | Quality Points | |--------|-------|-------------|---------|----------------| | English | A | 4.0 | 3 | 12.0 | | Maths | B+ | 3.3 | 4 | 13.2 | | History | A− | 3.7 | 3 | 11.1 | | Biology | B | 3.0 | 4 | 12.0 | | Art | A | 4.0 | 2 | 8.0 | | Total | | | 16 | 56.3 |
GPA = (56.3) / (16) = 3.52
Weighted GPA
Weighted GPA gives extra grade points for more challenging courses — honours, Advanced Placement (AP), and International Baccalaureate (IB) classes.
Common weighting system:
| Course Level | A = | B = | C = | |-------------|-----|-----|-----| | Regular | 4.0 | 3.0 | 2.0 | | Honours | 4.5 | 3.5 | 2.5 | | AP / IB | 5.0 | 4.0 | 3.0 |
Worked Example (Weighted)
| Course | Level | Grade | Points | Credits | Quality Pts | |--------|-------|-------|--------|---------|------------| | AP Calculus | AP | A | 5.0 | 4 | 20.0 | | AP English | AP | B | 4.0 | 3 | 12.0 | | Honours History | Honours | A | 4.5 | 3 | 13.5 | | Regular Biology | Regular | B+ | 3.3 | 4 | 13.2 | | Regular Art | Regular | A | 4.0 | 2 | 8.0 | | Total | | | | 16 | 66.7 |
Weighted GPA = (66.7) / (16) = 4.17
Weighted GPAs above 4.0 are common for students taking multiple AP courses.
Cumulative vs Semester GPA
Semester GPA: Calculated using only that semester's courses.
Cumulative GPA: Calculated across all completed semesters. This is what appears on transcripts and what colleges and employers see.
To calculate cumulative GPA, include all courses from all semesters in the formula — don't average the semester GPAs, as semesters may have different total credit hours.
GPA Benchmarks
| GPA | Meaning | |-----|---------| | 4.0 | Perfect — straight As | | 3.7+ | Excellent — A/A− range | | 3.5+ | Honours threshold at many schools | | 3.0+ | Good standing — B average | | 2.0+ | Satisfactory — minimum for graduation at most schools | | Below 2.0 | Academic probation at most schools |
For college admissions in the US, the average GPA at highly selective schools is around 3.9–4.0 (unweighted); at moderately selective schools, 3.5–3.8.
How One Grade Affects Your GPA
If your cumulative GPA is 3.4 after 60 credit hours and you're planning your next semester (15 credits), here's how different performance affects it:
| Next Semester Average | New Cumulative GPA | |----------------------|--------------------| | 4.0 (straight As) | 3.53 | | 3.7 (A−/A mix) | 3.51 | | 3.3 (B+/A− mix) | 3.47 | | 3.0 (straight Bs) | 3.43 | | 2.7 (B−/B mix) | 3.40 |
It takes many credit hours of strong performance to meaningfully raise a low cumulative GPA — which is why early semesters matter so much.
Calculate Your GPA Now
Our GPA calculator lets you enter all your courses, grades, and credit hours to get your exact GPA instantly — including semester and cumulative calculations.