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Final grade, to the decimal.

A weighted grade calculator that handles any class structure. Add a row for every assignment, exam, and quiz — see your current grade and letter, and find out exactly what you need on the final to land on a target.

How it worksReal-time

Inputs

Assignments

Total weight65% / 100%
#1
%
%
#2
%
%
#3
%
%

Final-exam target (optional)

%
%

You need 90.3% on the final to hit a 90% overall.

Current grade
89.85%
Letter
B+
Weight remaining
35%

Current weighted grade

3 rows · 65% counted

89.85%

Weighted average of every row whose weight is greater than zero.

Letter

B+

Σ(grade × weight)
5,840
Total weight
65%
Weight remaining
35%

Final exam target

To finish at 90% you need

90.3%on the final · letter A-
Current grade
89.85%
Letter · B+
Weight covered
65%
35% still ungraded
Σ(grade × weight)
5,840
÷ 65 = 89.85

Working

Step-by-step

Weighted average
RowGradeWeightGrade × Weight
1Homework
9220%1,840
2Midterm
8425%2,100
3Project
9520%1,900
Totals—65%5,840
Weighted average = 5,840 ÷ 65 = 89.85%

Field guide

How to calculate your final grade: by hand or here.

A “weighted” grade is one where different assignments count for different shares of your final score. A 5-question quiz worth 5% of the course and a 3-hour final worth 30% don't move the needle equally — even if you got the same percentage on both. The fix is simple arithmetic: multiply each grade by its weight, add the products, divide by the total weight. That's the weighted average.

The weighted-average formula

For any number of graded items, the weighted average is:

grade = Σ ( scorei × weighti ) ÷ Σ weighti

Each weight can be in any consistent unit. Options include percentages, point values, or fractions. As long as you use the same unit on top and bottom, the math works. This calculator uses percentages (so a 25% midterm enters as 25), which is what almost every syllabus uses.

Worked example: calculate a grade by hand

Say a syllabus is structured like this:

  • Homework: 92%, weight 20%
  • Midterm: 84%, weight 25%
  • Project: 95%, weight 20%
  • Final: not yet taken, weight 35%

Step 1. Multiply each completed grade by its weight:

92 × 20 = 1,840
84 × 25 = 2,100
95 × 20 = 1,900
─────────────────
sum = 5,840 (call this S)

Step 2. Add the weights you've used so far: 20 + 25 + 20 = 65. That's 65% of the course already accounted for.

Step 3. Divide: 5,840 ÷ 65 ≈ 89.85. Your current weighted grade is 89.85% or a B+ on the standard letter scale.

What you need on the final exam

The harder question — the one this calculator was really built for — is what score you need on the remaining final exam to hit a particular overall grade. The trick is to think in absolute %-points of the course, not in row-averages.

completedContribution = Σ ( scorei × weighti ) ÷ 100

scorefinal = ( target − completedContribution ) × 100 ÷ weightfinal

Continuing the example, the completed work contributes 5,840 ÷ 100 = 58.4 percentage points toward the full 100% of the course. To finish at 90% overall when the final is worth 35%:

scorefinal = (90 − 58.4) × 100 ÷ 35
              = 31.6 × 100 ÷ 35
              ≈ 90.29%

So a ~90.3% on the final nets the desired 90% overall. If the final is worth less (say 20%) the same 90% target needs an impossible (90 − 58.4) × 100 ÷ 20 = 158% on the final, which the calculator will flag in red. If the final is worth more (say 60%) you only need (90 − 58.4) × 100 ÷ 60 ≈ 52.7%.

Different grading systems explained

Most US K-12 and college courses use one of three setups:

  • Pure weight (this calculator): each category has a fixed % of the final grade. The 92% and the 84% above weren't the same because their weights differed.
  • Total points: every assignment is worth a fixed number of points, and the final grade is your total points ÷ total possible. That's really just a weighted average where the “weight” of each item is its point value. Enter point values in the Weight field and percent scores in Grade — it works the same.
  • Categories with internal averaging — homework gets averaged together, then that average counts for 30% of the course. To use this calculator, compute the in-category average yourself first, then enter that single number with the category's weight.

The standard letter grade scale

US college-style cutoffs (each calculator may use small variants. Check your syllabus):

  • A+ 97–100 · A 93–97 · A- 90–93
  • B+ 87–90 · B 83–87 · B- 80–83
  • C+ 77–80 · C 73–77 · C- 70–73
  • D+ 67–70 · D 63–67 · D- 60–63
  • F below 60

Common pitfalls

  • Weights that don't add to 100%. The tool will tell you. If your assignment list adds up to 98% rather than 100%, your weighted average will be calculated correctly across the rows you entered, but the “final exam target” math assumes the missing weight equals the final's weight. Make sure row weights + final weight = 100%.
  • Confusing percent and points. If your syllabus says “the project is worth 100 points and the final is worth 200 points,” just put 100 and 200 in the Weight column directly, the formula works with any consistent unit.
  • Counting an assignment twice. If the homework category averages everything together for 30%, don't enter each homework as a separate 30% row — average them yourself first and enter one row with weight 30%.
  • Missing extra credit. Extra credit shifts the math. The easiest workaround is to add the extra-credit points to the score of an existing row, not create a new row, since EC is rarely “weighted” the same way.

Disclaimer

This is an unofficial study tool. Always verify your grade against your instructor's gradebook or your institution's LMS; different schools use different cutoffs, rounding rules, and curve policies that this calculator can't know about.