Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Calculate a final weighted course grade and letter grade from assignments, midterm, and final exam scores.
This tool calculates a final course grade by weighting each graded component (assignments, midterm, final exam) by its stated percentage of the total grade, then converts the result to a letter grade on a common A/B/C/D/F scale.
Enter each component's weight (from your syllabus) and your score on it. Your final weighted percentage and letter grade appear instantly.
The calculator multiplies each component's weight by your score, adds those products, and divides by the sum of the weights you entered. Because it divides by the total weight rather than assuming 100, a set of weights that adds up to something else still returns a proper weighted average. The letter grade is then assigned from the unrounded percentage using simple cutoffs: 90 or above is A, 80 or above is B, 70 or above is C, 60 or above is D, and anything below 60 is F. There are no plus or minus grades in this tool.
Final % = sum of (weight x score) / sum of weights. Letter: A at 90+, B at 80+, C at 70+, D at 60+, otherwise F.
Suppose assignments are worth 30 percent and you scored 85, the midterm is worth 30 percent and you scored 78, and the final exam is worth 40 percent and you scored 82. The weighted sum is 25.5 + 23.4 + 32.8 = 81.7, and since the weights total 100, your final grade is 81.7 percent, which is a B. To see the effect of the exam, imagine you had scored 92 on the final instead: 25.5 + 23.4 + 36.8 = 85.7 percent. Because the final carries the largest weight, a ten-point change on it moves the overall result by four points, while the same ten-point change on assignments would move it by three.
Only three components are provided. If your syllabus has more categories, such as participation, labs or a paper, combine them into the closest fields or leave the unused weight out; since the tool divides by the weights entered, leaving out a category simply recalculates your grade on what is included, which will not match your official grade until every part is counted. Enter weights as whole percentages like 30, not as decimals like 0.3, and make sure each score is a percentage, not raw points. If you have points instead, divide earned points by possible points and multiply by 100 first. A component you have not yet completed should not be entered as zero unless you want to model failing it, since a zero drags the average down sharply.
Also watch the borderline cases. The tool assigns letters from the unrounded percentage, so 89.995 shows as 90.00 but is treated as a B because it is still below 90. Your instructor may round differently, so check the syllabus.
This is an estimate based on the numbers you supply. It does not include extra credit rules, dropped lowest scores, curves, minimum-score requirements for passing, or plus/minus scales. Your instructor and the institution's official grading policy decide the grade of record, so confirm with them when a grade decision matters, for example for scholarships, prerequisites or academic standing.
The tool normalizes by the total weight you enter, so it still produces a correct weighted average even if your three components don't sum to exactly 100 (e.g. if there are more components you're leaving out).
Not necessarily -- grading scales vary by institution. This tool uses a common reference scale; check your syllabus or institution's official policy for the scale that applies to your actual grade.
Yes, by trial. Enter your current scores, then change the final exam score until the final percentage reaches the level you want. The tool does not solve for it directly.
No. It returns only A, B, C, D or F using cutoffs at 90, 80, 70 and 60. Check your syllabus for how plus and minus grades are assigned.
Combine related categories into the three fields or leave some out. Leaving out a category means the result reflects only what you entered, so it may not match the official grade.
Enter percentages. If you have points, divide earned by possible points and multiply by 100 before entering the score.