Math

Grade Calculator

Find out what you need on your final exam, or calculate a weighted average across categories, and see the letter grade it works out to.

Your grade

Final Grade NeededWeighted Average

Score needed on the final

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If you score 100% on the final

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If you score 0% on the final

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Show the math

Estimate only — always check your syllabus or instructor's own grading policy, since some courses drop lowest scores, curve grades, or weight categories differently than a simple linear formula.

What grade do I need on my final?

Your overall grade is a weighted blend of your current work and the final: desiredGrade = currentGrade × (1 − finalWeight) + finalScore × finalWeight. Solving for the unknown final score gives requiredScore = (desiredGrade − currentGrade × (1 − finalWeight)) ÷ finalWeight. If that number comes out above 100%, the target isn't reachable even with a perfect score; if it's 0% or below, you've already secured it regardless of how the final goes.

Worked example: you have 84% going into a final worth 25%, and you want a 90% (an A−) overall. Your coursework already locks in 84 × 0.75 = 63 points. You need 90 − 63 = 27 more from the final, and 27 ÷ 0.25 = 108%, so an A− is out of reach without extra credit. Aim for 85% (a B) instead and you need (85 − 63) ÷ 0.25 = 88% on the final. The two cards under the result show the best and worst overall grade the final can leave you with.

Weighted grade averages

A weighted grade multiplies each category's score by its weight, sums those products, and divides by the total weight — so a 20%-weighted homework average affects your overall grade far less than a 50%-weighted exam average. Enter each category as a score and weight pair; this calculator normalizes by whatever the weights actually sum to, so it still works even if your categories don't add up to exactly 100%.

How much will my grade change?

A category can only move your overall grade by up to its own weight — a final worth 15% can shift your grade by at most 15 percentage points in either direction, no matter how extreme your score on it is. This is why a strong final can rescue a middling semester, but rarely erase it entirely, and why a single low-weight quiz barely moves the needle either way.

Letter grade percentages

Most US high schools and colleges use a plus/minus scale like the one below, and the calculator uses it for the letter it shows. Some schools use a simpler 90/80/70/60 scale without plus and minus grades, and some set A at 94 or 95, so treat this as typical rather than universal. The 4.0-scale points are what a GPA calculator averages across your courses.

Letter	Percent	4.0 scale
A+	97–100+	4.0
A	93–96	4.0
A-	90–92	3.7
B+	87–89	3.3
B	83–86	3.0
B-	80–82	2.7
C+	77–79	2.3
C	73–76	2.0
C-	70–72	1.7
D+	67–69	1.3
D	63–66	1.0
D-	60–62	0.7
F	Below 60	0.0

If your scores are in points rather than percentages, divide points earned by points possible first (43 out of 50 is 86%); the percentage calculator does that in one step.

Building a grade calculator in a spreadsheet

For a weighted average in Excel or Google Sheets, use =SUMPRODUCT(scores, weights) / SUM(weights) across two columns. For "what score do I need," either rearrange the same formula algebraically for the unknown score, or use Excel's Goal Seek (Data → What-If Analysis → Goal Seek) to solve it numerically. This calculator does both without any setup. If every assignment counts equally, you don't need weights at all: a plain mean of the scores, which the average calculator gives you, is the grade.

Frequently asked questions

What's the formula for the grade I need on a final exam?

Use the "Final Grade Needed" mode above: enter your current grade, how much the final is worth, and the grade you're aiming for. The formula is requiredScore = (desiredGrade − currentGrade × (1 − finalWeight)) ÷ finalWeight — this calculator solves it instantly and tells you if the target is realistically reachable.

What will my grade be, or what if I score X on the final?

Enter your current grade and the final's weight, then try different "desired grade" values in the Final Grade Needed mode to see what score each one requires — or flip the question around: your actual final grade is currentGrade × (1 − finalWeight) + yourFinalScore × finalWeight, so plug in a hypothetical final score as the desired grade to reverse-check.

How much will my grade drop or go up after the final?

Your grade moves toward whatever you score on the final, weighted by how much it's worth — a final worth 20% can only move your overall grade by up to 20 percentage points in either direction, regardless of how extreme your score on it is. The "already guaranteed" message in this calculator tells you when your grade genuinely can't drop below a certain point no matter what happens on the final.

Can my grade go above 100% with extra credit?

Yes, if your teacher counts extra credit on top of the normal points. Earning 105 points out of 100 is a 105% running grade, and this calculator accepts a current or target grade up to 150% so you can plan around it. Whether anything above 100% carries into the final course grade depends on your instructor's policy.

What percentage is a passing grade?

On the usual US scale, 60% (a D−) is the lowest passing grade and anything below is an F. Many schools and colleges, though, require a C (70% or 73%, depending on the scale) to count a course toward a major or as a prerequisite. Your syllabus or student handbook has the exact cutoff.