How semester grades are calculated
Definition
Semester grade
The composite grade for a half-year of coursework, calculated by combining quarter (or term) grades plus mid-term or final exam scores using a school-specific weighted formula.
US schools rarely just average quarters. The semester grade is a weighted combination of two quarter grades plus a final exam (and sometimes a midterm). The exact weighting depends on the district. Three common formulas:
- 40/40/20 — Q1 40%, Q2 40%, final 20%. The most common high school formula.
- 45/45/10 — Q1 45%, Q2 45%, final 10%. Used when finals are low-stakes.
- 40/40/10/10 — Q1 40%, Q2 40%, midterm 10%, final 10%. Common in courses with mandatory midterm.
- Default formula
- 40 / 40 / 20 (Q1 / Q2 / final)
- Letter scale
- 10-point (93+ = A, 90-92 = A-, 87-89 = B+)
- Common variants
- 45/45/10, 40/40/10/10, 50/50
- Where to find your formula
- Course syllabus or student handbook
Worked example
Using the 40/40/20 formula with Q1 = 90%, Q2 = 85%, final = 78%:
(90 × 40) + (85 × 40) + (78 × 20) = 3600 + 3400 + 1560 = 8560 ÷ 100 = 85.6% → B
Related tools
- Final grade calculator — what you need on the final to hit a target.
- Grade calculator — for ongoing assignment-weighted averages.
- Semester GPA calculator — combine semester letter grades across multiple courses into a GPA.
- Cumulative GPA calculator — roll multiple semester GPAs into one.