Grade Calculator
This free grade calculator works out your overall percentage and letter grade in a class from weighted categories like homework, quizzes, and exams. Add each category with its weight and your score, and your overall grade updates instantly. Nothing you enter is sent anywhere or stored.
How to Use It
- Enter each grading category with its weight and your score.
- Use "Add category" to add more rows, or the "Delete" button to remove one.
- Your overall grade and letter grade appear instantly as you type.
How It Works
Your overall grade is a weighted average: each category's score is multiplied by its weight, those are all added together, and the total is divided by the sum of the weights actually entered. This is exactly why weights don't need to add up to 100% for the result to be correct. Dividing by whatever they actually total normalizes the result automatically.
Formula
overall grade = sum of (score × weight) ÷ sum of weights entered
A worked example: Homework worth 20% of the grade at a score of 85%, Quizzes worth 15% at 78%, Exams worth 40% at 90%, and a Final Exam worth 25% at 88%. Multiplying each score by its weight gives 1,700, 1,170, 3,600, and 2,200, which add up to 8,670. The weights total exactly 100, so dividing gives an overall grade of 86.70%, a B on the standard scale below.
| Percentage range | Letter grade |
|---|---|
| 90% and above | A |
| 80% to 89% | B |
| 70% to 79% | C |
| 60% to 69% | D |
| Below 60% | F |
Everything runs client-side in your browser. No grades you enter are sent anywhere or stored.
Frequently Asked Questions
Do my category weights need to add up to exactly 100%?
No. The calculator divides by whatever your weights actually total, so a set of weights that adds up to 80% or 120% still produces a correctly weighted grade, proportional to the weights you entered. The live "Total weight" readout below the categories is there so you can double check your own numbers against your syllabus, not because a different total breaks the math.
Is the letter grade scale (A, B, C, D, F) the same everywhere?
No. This calculator uses the most common US 10-point scale (90 and up is an A, 80 to 89 is a B, and so on), but plenty of schools and instructors use different cutoffs, or add plus/minus grades on top. Check your own syllabus if you need the letter grade to match your class exactly. The percentage itself is calculated the same way regardless.
What happens if I leave a category at 0% weight?
It's excluded from the calculation entirely, not treated as a category worth zero points. This is useful for a category you haven't been graded on yet, like an upcoming final, since leaving its weight at 0 keeps your current grade based only on what's actually been scored so far.
Can I enter a score over 100%?
Yes. A score above 100% is treated as a real value, not an error, since extra credit legitimately pushes a category above a perfect score. It factors into the weighted average the same way any other score does.
How is this different from the GPA Calculator?
This tool calculates one weighted grade within a single class, built from that class's own categories (homework, exams, and so on) and their percentage scores. The GPA Calculator works at a different level entirely: it averages letter grades across multiple classes, weighted by each class's credit hours, to produce a cumulative GPA. Neither one substitutes for the other.
Why enter a percentage score instead of points earned out of points possible?
Percentage keeps every category on the same 0 to 100 scale regardless of how many points each assignment was actually worth, so a quiz graded out of 20 points and a final graded out of 200 points combine correctly without any extra conversion. If you have a raw score, dividing points earned by points possible and multiplying by 100 gives you the percentage to enter.
Does the order I enter categories in matter?
No. The weighted average is the same regardless of the order the categories are listed in. Order them however makes the most sense to you, matching your syllabus is usually the easiest to double check.