Grade Calculator

Compute your current grade, required final exam score, and weighted course average. Supports points or percentage grading, custom weights, and what‑if scenarios.

Grading system:

1. Enter your assignments

Group assignments into categories (homework, quizzes, exams, etc.). You can use either points or percentages.

Category Weight (%) Scores Avg

0% of 100% assigned

How this grade calculator works

This grade calculator is designed for real‑world classes where you have multiple categories (homework, quizzes, labs, exams) with different weights. It supports:

  • Points or percentage grading for each assignment.
  • Weighted categories that sum to 100%.
  • Final exam score needed to reach a target grade.
  • What‑if scenarios for upcoming assignments or missed work.
  • Custom letter grade scale to match your school.

1. Weighted grade formula

For each category \(i\):

Category average (percent):

\[ \text{CategoryAvg}_i = \begin{cases} \frac{\sum \text{PointsEarned}}{\sum \text{PointsPossible}} \times 100 & \text{(points mode)} \\ \text{mean of assignment percentages} & \text{(percent mode)} \end{cases} \]

Overall course grade:

\[ \text{CourseGrade} = \sum_i \left( \text{CategoryAvg}_i \times \frac{\text{Weight}_i}{100} \right) \]

2. Final exam grade needed

Let:

  • \(C\) = current course grade (in %)
  • \(T\) = target course grade (in %)
  • \(w\) = final exam weight as a decimal (e.g. 30% → 0.30)
  • \(F\) = final exam grade needed (in %)

The weighted average after the final is:

\[ T = C \times (1 - w) + F \times w \]

Solving for \(F\):

\[ F = \frac{T - C \times (1 - w)}{w} \]

If \(F > 100\%\), the target is mathematically impossible; if \(F < 0\%\), you have already secured at least that target.

3. What‑if grade scenarios

To see how a single upcoming assignment affects your grade, we treat it as a new component with weight \(w\) and score \(S\):

\[ \text{NewGrade} = C \times (1 - w) + S \times w \]

Set \(S = 0\) to simulate missing the assignment.

Tips for accurate results

  • Make sure your category weights add up to 100%.
  • Only include graded assignments so far; leave future ones out.
  • Check your syllabus for special rules (dropping lowest quiz, extra credit, pass/fail thresholds).
  • Adjust the letter grade scale if your school uses plus/minus or non‑standard cutoffs.

Frequently asked questions

How do I use the points mode correctly?

In points mode, each assignment is entered as earned points / possible points (for example, 18 out of 20). The calculator sums all earned points and possible points within a category to compute the category percentage, then applies the category weight.

What if my teacher drops the lowest score?

This calculator does not automatically drop the lowest score, but you can simulate it easily: remove the lowest assignment from that category before entering your scores. The resulting average will match the “drop lowest” policy.

Can I mix points and percentages?

Within a single calculation, choose either points or percentages for consistency. If your syllabus mixes them, convert everything to one system first (for example, convert each score to a percentage) and then use the percentage mode.

Why doesn’t my result match the school portal exactly?

Schools sometimes use additional rules: rounding at each step, extra credit, participation, or special minimums for exams. This calculator uses straightforward weighted averages. If you suspect a difference, check your syllabus and grading portal for any special policies.