Grade Calculator - Weighted Scores & Letter Grades

The Grade Calculator builds a current course grade from completed assignments using either category weights or points earned over points possible. Enter each score and its weight (or points), and the calculator returns the weighted average, each category's contribution and an optional letter grade on an editable scale.

Weights that do not yet total 100% are handled as a running grade over completed work, which matches how a term looks mid-semester before the final exam lands.

Calculate a current grade from completed work

List each completed item with its score as a percentage or as points and with its syllabus weight. The calculator ignores empty rows and totals only what you entered. Confirm that category names and weights match the syllabus exactly; a midterm entered at 25 percent when the syllabus says 30 percent shifts every contribution downstream.

A current grade is only as complete as the work behind it. Remaining categories still move the final number; use the Final Grade Calculator when the question is what the final exam must score.

Apply the weighted grade formula

Course grade equals the sum of each score times its weight, divided by the sum of the weights used. Summing only completed items and dividing by their weight total keeps a mid-semester figure honest when later categories are still empty.

When weights already span the full course and every category has a score, the denominator is 1.0. grade = Σ(scoreᵢ × weightᵢ) / Σweightᵢ ```

Sum only completed items. Dividing by the sum of those weights (rather than always by 1.0) keeps a mid-term total honest when remaining work is still outstanding.

Example piece: a homework average of 90 at weight 0.20 contributes 18 points to a 100-point course scale when weights are taken as fractions of the full course.

Calculate a grade from points earned and possible

Points mode skips category weights and computes grade as total points earned divided by total points possible, times 100. Earning 430 of 500 possible points yields 86 percent. Use this mode when the syllabus is points-based rather than category-weighted, and do not mix leftover percentage weights from another class into the same grid.

grade = (Σ points earned / Σ points possible) × 100

Earned 430 of 500 possible → 430 / 500 × 100 = 86%. Use this when the syllabus is points-based rather than category-weighted. Mixing points mode with leftover percentage weights from another class is a common setup error; pick one scheme per course.

Calculate a grade with three weighted categories

With homework at 20 percent scoring 90, midterm at 30 percent scoring 80, and final at 50 percent scoring 85, the course total is 18 plus 24 plus 42.5, which equals 84.5 percent. On the default US letter scale that maps to a B. The final category contributes 42.5 course points, the largest block in the example.

If the final has not been taken yet, omit that row and use the incomplete-weight method in the next section, or jump to the Final Grade Calculator to solve for the exam score that hits a target. Entering a guessed final here produces a projected course grade, not a required-score plan.

grade = 90×0.20 + 80×0.30 + 85×0.50
      = 18 + 24 + 42.5
      = 84.5%

Letter on the default US scale (A ≥ 93, A− ≥ 90, B+ ≥ 87, B ≥ 83, …) → B. Contributions: homework 18, midterm 24, final 42.5. The final exam category carries the largest block of the course grade.

Handle weights that do not total 100 percent

Mid-semester you may have only homework and midterm completed while a 50 percent final remains. Enter the completed rows only and divide by their weight sum: 90 times 0.20 plus 80 times 0.30, divided by 0.50, equals 84 percent. That figure is a running average on work done so far, not the final course grade.

running = (90×0.20 + 80×0.30) / (0.20 + 0.30) = 42 / 0.50 = 84%

That 84% is the average on work done so far, not the final course grade. The Final Grade Calculator takes this running figure plus the final's weight when planning a target.

Convert a percentage to a letter grade

The default bands follow a common US plus-minus scale: A at 93, A-minus at 90, B-plus at 87, B at 83, and so on down to F below 60. Institutions vary widely, including 10-point bands with no plus-minus and pass marks at 50 or 65. Edit the thresholds to match the syllabus; the calculator applies the scale you set.

Letter	Minimum %
A+	97
A	93
A−	90
B+	87
B	83
B−	80
C+	77
C	73
C−	70
D+	67
D	63
D−	60
F	below 60

Institutions vary: some use 10-point bands with no plus/minus; some pass at 50 or 65. Edit the thresholds to match the syllabus. The calculator never invents an official transcript letter; it applies the scale you set.

See which assignment carries the grade

Each row shows contribution as score times weight on a full-course basis, or as a share of total points in points mode. Sorting by contribution size shows which category moves the course grade most. A 95 in a 5 percent quiz contributes 4.75 course points, while an 80 in a 40 percent exam contributes 32.

A 95 in a 5% quiz category contributes 4.75 course points. An 80 in a 40% exam contributes 32. Raising the exam helps more per percentage point of score improvement. That comparison is the practical use of the contribution column.

Syllabus matching checklist

Copy weights from the syllabus PDF rather than from memory. Watch for categories that drop the lowest quiz, replace a midterm with a final, or floor a failed lab at a minimum percentage. Those policies need a manual adjustment to the inputs; the basic weighted average will not invent them.

Extra credit belongs only where the syllabus puts it: as its own weighted row, as added points, or as a bonus after the weighted total. Putting bonus points into the wrong field double-counts or dilutes other categories.

Mid-term projections versus locked grades

A running weighted average is a projection, not a locked transcript line. Categories still empty can move the course grade by tens of points when they carry large weights. Treat mid-term dashboards as planning tools: useful for triage, not for celebrating a final letter early.

When a syllabus floors or caps a category (for example, quiz average cannot exceed 100 after extra credit), apply that rule to the category score before weighting. Feeding an uncapped 110 percent quiz average into the weighted formula invents course points the syllabus never granted.

Dropped scores

If the syllabus drops the lowest quiz, remove that quiz row from the weighted list before computing the average, or the running course grade will sit too low relative to the portal. Document which attempt was dropped, and on which date, so a later audit or grade dispute can reproduce the same category average exactly.

Frequently asked questions

Summary

The Grade Calculator computes a current course percentage from weighted categories or from points earned over points possible, shows each row's contribution and maps the result to an editable letter scale. Three categories at 20%, 30% and 50% with scores 90, 80 and 85 produce 84.5% (B on the default scale).

Incomplete weights yield a running average over completed work. For the score still required on a final exam, switch to the Final Grade Calculator; for credit-hour averages across courses, use the GPA Calculator.