Weighted Grade Calculator

How this is calculated

A syllabus that says “Homework 20%, Quizzes 15%, Midterm 25%, Final 40%” is describing a weighted average. Each component contributes points equal to your score on it times its weight, and the course grade is the sum of those contributions. It is not the plain average of your scores — that only matches when every weight is identical.

Worked through with the example the page loads with. Homework is two marks, 7/10 and 44/50 — 51 points of 60, so 85% — and on a 20% weight that contributes 17 points. Quizzes are 24 of 30, so 80%, contributing 12. The midterm at 84% on 25% contributes 21, and the final at 88% on 40% contributes 35.2. Added up: 17 + 12 + 21 + 35.2 = 85.2%.

The one choice this tool can't make for you

When a single component holds several marks, there are two defensible ways to combine them, and they disagree whenever the marks are out of different totals. The homework above is exactly that case:

Six points of difference on that one component moves the whole course grade from 85.2% to 84.0%. Neither rule is wrong in general — a category written in raw points implies the first, and one described as “the average of your quizzes” implies the second. So the rule is a labelled input rather than a hidden default, and the tool prints what the other rule would have produced whenever the two differ. If your syllabus doesn't settle it, that is a question for your instructor, and a fair one to ask.

What it assumes

• The weights you enter are the ones that count. They are used exactly as typed and never rescaled to total 100. If yours total something else, the tool says so rather than quietly normalizing — a total that isn't 100 is a syllabus to re-read, not a rounding error to hide.
• A blank mark means not graded yet, not zero. That weight is left out of the average entirely and the result is labelled as covering only the graded portion. Typing 0 means a zero was earned, which is a different and much worse number.
• A bare number is a percentage. 88 is read as 88 out of 100, so it means the same thing under either averaging rule. Anything with a slash is read as points: 17/20 is 85%.
• Nothing is capped. A mark above its total — 22/20 after extra credit — comes through as 110% and raises the component above 100, because that is what an extra-credit mark actually does to a grade.

Where this stops being right

• Rules your syllabus states in prose. Dropped lowest scores, curves, a final that replaces a midterm, a minimum exam score required to pass regardless of the average — none are applied here. For a dropped lowest quiz, leave that mark out of the row; for a curve, enter the curved mark.
• Categories weighted inside themselves. If one assignment inside a category is worth more than the others by rule rather than by points, split it into its own row with its own share of the weight.
• Letter grades. The percentage cut-off for each letter is set by your institution — an A− starts at 90 in one course and 92 in another, and some schools have no minus grades at all. Read your own cut-offs off your own syllabus and compare them to the percentage above.
• This is not your official grade. Your instructor records it and your registrar keeps it. If either disagrees with this page, they are right.

Sources

A weighted mean needs no authority. What does need one is the premise underneath it: that the weights printed in your syllabus are the rule your grade is actually computed under, and that they can't be moved afterwards. That is institutional policy, and it's written down.

Penn State University Faculty Senate, Policy 47-20, Basis for Grades: “The instructor should provide written (paper or electronic form) notification of the basis for grades to students on or before the first class meeting,” and “any changes in that basis should likewise be presented to students in writing.”

University of Toronto Governing Council, University Assessment and Grading Practices Policy (in force 1 January 2020): the instructor “shall make available to the class … the methods by which student performance shall be evaluated,” including their relative weights, and once those are known “the instructor may not change them or their relative weight without the consent of a simple majority of students attending the class.”

Both are cited as published, verifiable examples rather than as policies governing your course — your own registrar or student handbook will state the equivalent rule. The point they establish is the one this tool is built on: the document in your hand is the primary source, and the calculator's only job is to do its arithmetic in the open.

Last reviewed: August 2026