About this tool
A weighted grade calculator for whole-course grading. List the categories on your syllabus (Homework, Quizzes, Tests, Final, and so on), tell it what each is worth and what you've earned so far, and it gives you the overall percentage and letter grade. There's also a planner: mark which categories aren't graded yet and pick a target, and it tells you the average you need across the rest to land on it.
Everything runs in the browser. No accounts, no analytics, nothing leaves your device. Use it once at midterm, use it daily as the semester closes, either way your numbers stay on your screen. If you're grading a single test by number of questions right and wrong, the EZ Grader is the per-test sibling of this tool. If you're calculating cumulative GPA across many courses instead of one course grade, see the GPA Calculator.
How it works
Weighted grading turns categories of different sizes into one overall number. The formula is simple: multiply each category's weight by its grade, add the results, divide by the total weight. With weights that add to 100, dividing by 100 gives a percentage directly. The calculator does this on every keystroke, so you can sketch what-if scenarios without clicking anything.
Worked example using the Load sample data:
- Homework — weight 20%, grade 92%
- Quizzes — weight 20%, grade 85%
- Tests — weight 40%, grade 78%
- Final — weight 20%, grade 82%
The weighted contributions are 20 × 92 = 1840, 20 × 85 = 1700, 40 × 78 = 3120, and 20 × 82 = 1640, for a total of 8300 weighted points. Divide by the total weight of 100 and the course grade is 83.0%, which lands in the B band on the default scale. Drop the Tests grade to 70% and the same math gives 79.8% — a fraction of a point below B. That's the kind of cliff the calculator surfaces immediately.
The default letter scale is A at 90 or higher, B at 80, C at 70, D at 60, F below. That matches most US K-12 and introductory college courses. The percentage is the source of truth either way — if your course uses a different scale, read the percentage and apply your own cutoffs.
The What do I need on the rest? planner reverses the question. Tick the categories that haven't been graded yet, type the percentage you want to finish with, and the planner solves for the average across those open categories. If the answer comes back over 100%, the target is no longer mathematically possible; that's a useful thing to know early.
Common gotchas
Most wrong answers come from data going in, not from the formula. A few patterns to watch for:
- Weights aren't on the syllabus. Some instructors describe the grade in words ("tests are the bulk of your grade, homework matters too") without numbers. Without numbers, no calculator can give you a number — ask the instructor for the percentages before trusting any output. Plausible guesses are not a substitute.
- Dropped lowest score. Many courses drop the lowest quiz or homework grade. Compute the category average after dropping the lowest, then enter that average here. The calculator doesn't track individual assignments; it works at the category level.
- Extra credit. Extra credit comes in two flavors. If it's added to a specific category's grade (5 bonus points to your test average), bake it into the category grade you enter. If it's a separate weighted bucket (a 2% extra-credit category on top of 100%), add it as a new row — the calculator handles weights summing to more than 100 and will flag it so you can confirm.
- Mid-semester estimates lie. Entering a category grade based on one assignment is almost always an over- or under-estimate. The number stabilizes as more grades land. A 100% on the first quiz isn't a 100% Quiz category yet; weight your confidence accordingly.
- The 100% target trap. If you mark a category open and ask the planner for a target you've already passed the ceiling on, the required-average answer goes above 100. That's the math telling you to either lower the target or accept that the prior grades have locked in a maximum. It's not a bug.
Frequently asked questions
How do I find my category weights?
The syllabus is the source. Most college and high school syllabi list a breakdown like Homework 20%, Quizzes 20%, Tests 40%, Final 20%. If the syllabus is vague, ask the instructor before guessing — vague weights are a common source of end-of-term surprises.
What if my weights don't add to 100%?
The calculator still works — it divides weighted points by the total weight you entered, so the math stays honest. A warning appears under the rows so you can double-check whether you missed a category or have legitimate extra-credit weight on top.
How is the letter grade decided?
Default thresholds are A ≥ 90, B ≥ 80, C ≥ 70, D ≥ 60, F < 60 — the most common US scale. The percentage is the source of truth; if your course uses a 7-point or plus/minus scale, apply your own cutoffs to the percentage shown.
Is this for a single assignment or a whole course?
Whole course. Each row is a category, not one assignment. For grading one test by questions right and wrong, use the EZ Grader instead.
How does the "What do I need on the rest?" planner work?
Mark any row "not yet graded," enter the percentage you want to finish with, and the planner returns the average required across all open categories combined. If the answer is above 100 the target is no longer reachable; if it's below 0, you've already locked it in.
Is my data private?
Yes. The calculator runs entirely in your browser. Nothing you type is sent to a server, stored, or logged. Close the tab and it's gone.