Calculate weighted semester grade from category scores
With 92 in homework, 84 in quizzes, 88 in exams and 100 in participation, weighted 25, 15, 50 and 10 percent, your semester grade is 89.6%. Enter the four category scores and their syllabus weights, which must total exactly 100%. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Homework score
- 92
- Homework weight
- 25
- Quizzes score
- 84
- Quizzes weight
- 15
- Exams score
- 88
- Exams weight
- 50
- Final grade
- 89.6
- Total weight
- 100
This weighted semester grade calculator combines homework, quiz, exam, and participation scores using the percentage weight assigned to each category. Enter every category score and its share of the course grade, and the calculator returns the final semester percentage together with each category's contribution. The calculation is deterministic, transparent, and suitable for quick checks or automated academic tools.
Enter category scores and weights correctly
Start with the percentage score currently earned in each of the four supported categories: homework, quizzes, exams, and participation. A score of 92 means that 92 percent of the available points in that category were earned; it does not mean the category contributes 92 points to the semester result. Next, enter the syllabus weight for each category.
For example, homework might carry 25 percent, quizzes 15 percent, exams 50 percent, and participation 10 percent. All scores and weights must be finite numbers between 0 and 100. A category may have a zero weight when it is listed but does not affect the semester grade.
However, no score or weight may be negative or exceed 100. Use the weights from the official course grading policy whenever possible. If an instructor changes the policy during the term, update the relevant weights before relying on the result for planning or reporting.
Understand the weighted calculation
The calculator converts each category weight from a percentage into a fraction and multiplies that fraction by the category score. If exams are worth 50 percent and the exam score is 88, exams contribute 44 points to the final semester percentage. The same operation is performed for homework, quizzes, and participation, and the four contributions are added.
Results are stabilized to six decimal places to prevent distracting floating-point artifacts while preserving useful precision. This is a weighted sum, not an unweighted average of the four category scores. Consequently, a strong result in a heavily weighted category changes the final grade more than the same improvement in a lightly weighted category.
Check the 100 percent rule and interpret the result
A complete semester grading plan must allocate exactly 100 percent across the four categories. The calculator checks that rule before producing any grade. If the supplied weights total 95 or 105, it returns an invalid input error that reports the received total.
This prevents a common spreadsheet mistake in which a missing category or duplicated weight silently produces a plausible but incorrect number. Decimal weights are supported, and a very small tolerance is used only to accommodate normal binary number representation; it is not a way to accept an incomplete grading plan. Converting that percentage to a letter grade depends on the instructor's grading scale and is intentionally outside this calculation.
Also remember that category scores can change as assignments are added, dropped, curved, or reclassified. Recalculate whenever the underlying gradebook or syllabus weights change, and consult the official course record when a result affects an academic decision.
What you can do with it
Estimate a current semester result
Combine the latest category percentages with the syllabus weights to see the weighted grade represented by the current gradebook.
Audit a spreadsheet formula
Compare the returned category contributions with a manually maintained workbook and catch missing, duplicated, or incorrectly scaled weights.
FAQ
What happens if the weights do not total 100%?
The calculation stops and returns an invalid input error showing the weight total that was received.
Can a category have a weight of zero?
Yes. Its score is still validated, but it contributes zero points to the final grade.
Can I use decimal scores and weights?
Yes. Finite decimal values from 0 through 100 are accepted for every score and weight.
Does the result include a letter grade?
No. Letter-grade thresholds vary by school and instructor, so the capability returns the weighted percentage only.
Why is my semester grade not the average of my four scores?
Because it is a weighted sum, not a plain average. Exams worth 50% with a score of 88 add 44 points, while participation worth 10% at 100 adds only 10, so heavily weighted categories move the result most.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/edu/semester-grade-weighted \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"homework_score":92,"homework_weight":25,"quizzes_score":84,"quizzes_weight":15,"exams_score":88,"exams_weight":50,"participation_score":100,"participation_weight":10}'const res = await fetch("https://api.kit.forhosting.com/edu/semester-grade-weighted", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"homework_score": 92,
"homework_weight": 25,
"quizzes_score": 84,
"quizzes_weight": 15,
"exams_score": 88,
"exams_weight": 50,
"participation_score": 100,
"participation_weight": 10
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/edu/semester-grade-weighted",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"homework_score": 92,
"homework_weight": 25,
"quizzes_score": 84,
"quizzes_weight": 15,
"exams_score": 88,
"exams_weight": 50,
"participation_score": 100,
"participation_weight": 10
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/edu/semester-grade-weighted", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"homework_score":92,"homework_weight":25,"quizzes_score":84,"quizzes_weight":15,"exams_score":88,"exams_weight":50,"participation_score":100,"participation_weight":10}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"homework_score":92,"homework_weight":25,"quizzes_score":84,"quizzes_weight":15,"exams_score":88,"exams_weight":50,"participation_score":100,"participation_weight":10}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/edu/semester-grade-weighted", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"homework_score": 92,
"homework_weight": 25,
"quizzes_score": 84,
"quizzes_weight": 15,
"exams_score": 88,
"exams_weight": 50,
"participation_score": 100,
"participation_weight": 10
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "edu.semester_grade_weighted",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
It also checks the grading plan before calculating: if the four weights do not add up to exactly 100%, the request returns a clear input error instead of a misleading grade.
Understand the weighted calculation
The response includes the final_grade as well as a contributions object, so the arithmetic can be inspected rather than treated as a black box. The returned total_weight confirms the validated basis of the calculation.
Check the 100 percent rule and interpret the result
Treat final_grade as a percentage under the inputs you supplied.
Integration use cases
Power an academic dashboard
Use a deterministic API calculation to display consistent semester percentages while rejecting grading configurations that do not total 100%.
Technical questions
How much does the API request cost?
The API base price is $0.002 per request. The browser calculation is available through the tier A client.