Grade Calculator
Your current grade in a class, category by category. Enter what you scored, what it was out of, and what share of the final grade it carries — add a row for every line on the syllabus. If the weights do not add to 100%, this tool says so rather than quietly pretending they do.
Your graded categories
Schools disagree. A 93 is an A here and an A− wherever A starts at 94; a 90 is an A− here and a straight A on the ten-point scale. Check your syllabus.
3 graded categories weighted to 100% of the final grade, read against the plus/minus — a starts at 93 scale.
- Overall percentage
- 40.40%
- Letter grade
- F
- Weights entered
- 100%
- Weights used
- As entered
| Category | Score | Category % | Weight used | Points of grade |
|---|---|---|---|---|
| Homework | 85 / 100 | 85.00% | 20% | 17.00 |
| Midterm | 78 / 100 | 78.00% | 30% | 23.40 |
| Final | 0 / 100 | 0.00% | 50% | 0.00 |
How a weighted category grade is worked out
Each category becomes a percentage on its own, and those percentages are averaged with the syllabus weights deciding how loudly each one speaks.
sᵢ = earnedᵢ ÷ possibleᵢ × 100 • g = Σ(sᵢ × wᵢ) ÷ Σwᵢ- sᵢ
- Category i as a percentage — 85 out of 100 is 85, and 105 out of 100 is 105
- wᵢ
- The weight the syllabus gives category i
- g
- The overall percentage, then read against your scale
Dividing by Σwᵢ rather than by 100 is the whole difference between this and most grade calculators. When your weights already total 100 the two are identical. When they do not, dividing by the real total is the only sensible thing to do — and the only honest thing to do is then tell you it happened, which the result panel does. Silently normalising is how a syllabus typed as 20 / 30 / 40 returns a confident, wrong answer everywhere else.
The letter comes last. It is read off the percentage using the cutoffs you selected, and the lowest band has to start at 0 so every possible percentage lands somewhere.
Weighted categories and weighted points are not the same course
Take a class with five homework assignments worth 10 points each and two exams worth 100 points each. You get every homework point — 50 out of 50 — and 140 out of 200 across the two exams. The syllabus says homework is 50% of the grade and exams are the other 50%.
Weighted categories, which is what this calculator does and what that syllabus describes: homework is 100%, exams are 70%, so the grade is 100 × 0.5 + 70 × 0.5 = 85% — a B.
Weighted points, which is what a course does when it says “the class is out of 250 points”: everything goes in one pot, so the grade is (50 + 140) ÷ (50 + 200) = 190 ÷ 250 = 76% — a C.
Nine percentage points and a full letter grade apart, on identical work. The reason is that homework is 50% of the grade under the first scheme but only 20% of the points under the second — 50 points out of 250. If your syllabus lists percentages, use this calculator. If it lists a total points figure and no percentages, put every assignment in as one category instead, or give each category a weight equal to its point total and let the normalisation do the work.
And a dropped lowest score moves it again
Same class, now with four quizzes out of 20 each, weighted 30%. You scored 18, 17, 19 and 6 — that is 60 out of 80, or 75%. The syllabus drops your lowest quiz, so the category is really 54 out of 60, which is 90%. At a 30% weight that is the difference between 22.5 and 27 points of your final grade: four and a half points, or roughly a letter and a half at the boundaries.
The Drop my lowest score toggle in Advanced options cannot do that subtraction for you here, because these four quizzes are one combined row — 60 out of 80 — and the toggle only ever drops a whole row, never an assignment buried inside one. Do the subtraction first and enter the category as 54 out of 60, the same as always.
Split the same four scores into four separate rows instead — Quiz 1 through Quiz 4, 25% apiece, nothing else on the syllabus — and the toggle can reach them directly. Counting all four gives the identical 75% (18 + 17 + 19 + 6, out of 80). Turn the toggle on and it finds Quiz 4 at 6 out of 20 (30%, your lowest), drops it, and the remaining three renormalise to a plain average: (90 + 85 + 95) ÷ 3 = 90%. Same scores, a different row layout, and only one of the two lets the toggle do the work.
Extra credit that stands apart from any category behaves differently again. The homework-and-exams class further up landed on 85%, a B. Say the instructor also offers 2 points added to the final average for attending a review session, full marks for showing up. Entered as an Extra credit row in Advanced options — its own name, score and a 2-point weight — those 2 points add directly on top of the graded 85%, untouched by any normalising: 85 + 2 = 87%, a B+. Typing the same 2 points into the Homework or Exams category instead would have done something different — shared in whatever normalising that category's weight needed — which is exactly why bonus work that was never part of a category gets a row of its own.
What this calculator assumes
- Categories are weighted, not points. A category is worth its weight no matter how many points sit inside it. See the worked example above for when that matters.
- A row entered as 0 out of 100 is a zero you earned, not an assignment that has not happened. Remove the row or set its weight to 0 if you want your grade on marked work only.
- Weights that do not total 100 are scaled so they do, and the result says so and prints your original total. Nothing is normalised silently.
- Scores above the points possible are extra credit and are not capped. 105 out of 100 is carried through as 105%.
- An Extra credit row in Advanced options is a second, separate kind of bonus: its points add on top of the graded 100% pool instead of sharing in any normalising, so a few small rows there can carry the overall grade past 100% even when every graded category tops out at a clean 100.
- Drop my lowest score removes exactly one row — the lowest-scoring graded category — and never an extra-credit row or one already at 0% weight; with only one graded category it does nothing. Dropping the lowest of several assignments combined into a single category, or replacing a missed score with the final, is still yours to do before you type — enter the category as it stands after the rule.
- The letter is read off the percentage rounded to four decimal places. A school that rounds to a whole percent first can land a boundary case one band higher — an 89.6 that becomes a 90 there is still an 89.6 here.
Grade calculator FAQ
What is my grade if the final has not happened yet?
That depends on which question you are asking, and the two answers are far apart. Leaving the final in the list at 0 out of 100 treats it as a zero you have already earned — which is what most gradebooks show, and why a good student can see an F in week ten. Deleting the row instead leaves the weights adding to less than 100%, this tool scales them back up to 100%, and the percentage you get is your grade on the work that has actually been marked. Both are on this page; the result panel tells you which one you are looking at.
Do the category weights have to add up to 100%?
No, and this is where most grade calculators go wrong. If your weights total 90% or 110%, the arithmetic still works — every weight is scaled by 100 divided by your total before the average. The difference is that this tool prints your total and says it normalised, so a mistyped weight looks like a mistyped weight rather than a plausible grade. It also means you can type raw point totals (500, 300, 200) instead of percentages and get the same answer.
Why does my answer differ from the school gradebook?
Four usual suspects. One: your course weights points, not categories — check the syllabus for a total points figure rather than a list of percentages. Two: a drop-the-lowest rule you have not applied — turn on “Drop my lowest score” in Advanced options if the rule drops a whole category, or subtract by hand first if it is buried inside one combined category. Three: assignments that are not graded yet, which your gradebook may be excluding and you may be entering as zeros. Four: rounding — some student information systems round each category before combining, and some round only at the end.
Is a 93 an A or an A−?
It depends entirely on the school, which is why the cutoffs here are editable. On the plus/minus scale most common in the United States, A starts at 93, so a 93 is an A and a 92 is an A−. Plenty of schools start the A at 94, which makes the same 93 an A−. On the ten-point straight-letter scale, anything from 90 up is simply an A. Set the scale to match your syllabus before you read the letter.
Can I enter extra credit, or a score higher than the points possible?
Yes. A category of 105 out of 100 is a 105% category and is carried through at 105% — nothing is capped at 100. That is how extra credit actually behaves in most gradebooks: it lifts one category above full marks, and how much it moves your final grade depends on that category's weight.
How do I handle a category with no grades in it yet?
Set its weight to 0, or remove the row. Leaving it at 0 out of 100 with its real weight tells the calculator you scored zero on it, which is a different claim. A zero-weight row stays visible in the breakdown and contributes nothing, which is useful when you want to keep the full syllabus on screen.
Can this calculator drop my lowest quiz automatically?
Yes, with a caveat that matters: the “Drop my lowest score” toggle in Advanced options removes one whole row — the graded category where you scored lowest — not one assignment sitting inside a category that already combines several. If your quizzes are entered as a single combined row, the toggle cannot see the scores inside it; list them as separate rows instead if you want the toggle to reach them, as in the worked example above. It also never drops an extra-credit row or a row already at 0% weight, and it does nothing on a syllabus with only one graded category — there would be nothing left to grade.
How is an Extra credit row different from just typing a high score?
Typing 105 into a category worth 100 points makes that one category worth 105% — real, and carried through, but still subject to whatever normalising the rest of your weights need. An Extra credit row in Advanced options is a separate kind of bonus: its points add directly on top of the graded 100% pool, untouched by normalising, which is how a syllabus line like “3 points added to your final average” actually behaves. Use a score over 100% for one assignment that ran long; use an Extra credit row for bonus work that was never part of a category to begin with.
Sources and review notes
- NCES High School Transcript Study — the federal survey that collects real transcripts and has to convert each school to a common scale before it can compare them
- NCES Digest of Education Statistics — the standing reference for how grades and credits are recorded across US schools
There is no standards body for course grading, and that is the point: the arithmetic on this page is a weighted mean and cannot go stale, but the cutoffs that turn a percentage into a letter are set school by school. The same is true of drop-the-lowest and extra-credit rules in Advanced options — no accreditor mandates either one, individual instructors do, which is why both are toggles you turn on rather than defaults you have to opt out of. The sources above are the closest thing to an official acknowledgement that the scales differ. Your syllabus outranks all three.