Grade calculator
Calculate weighted grades from percentages, letters, or points, with a configurable percentage-to-letter scale.
Inputs
Grade 1
Grade 2
Grade 3
Results
Grade details
| Item | Grade | Weight | Weighted contribution |
|---|---|---|---|
| Grade 1 | 67.00% | 0.15 | 10.05% |
| Grade 2 | 75.00% | 0.35 | 26.25% |
| Grade 3 | 72.00% | 0.50 | 36.00% |
Grading scale (thresholds)
These minimum percentages map percentage and points results to letters. Values must decrease strictly from A+ through D-; F is anything below the D- minimum.
How to use this grade calculator
What this calculator does
This calculator estimates an overall weighted grade from up to 15 recorded results. It supports three common input styles: percentages, letter grades, and points earned out of points possible. In percentage and points modes, the numerical result is also translated to a letter using the editable grading thresholds below the calculator. In letter mode, letters are converted to grade-point values and averaged with the same weight formula. The result is a calculation aid, not an official transcript or course-policy decision; your instructor or institution may use different rounding, dropped assignments, category caps, extra credit, or special grading rules.
A weighted grade is a weighted mean: each grade is multiplied by its relative importance, the products are added, and that sum is divided by the total weight. This is closely related to how institutions weight grade points by course credits. The National Center for Education Statistics explains grade-point averaging and credit weighting, including why different schools may standardize grades differently.
When to use it
- Estimate a course average when assignments, exams, projects, or subjects have unequal weights.
- Check an unweighted average by entering the same weight, such as 1, for every grade.
- Convert a weighted percentage or weighted points result to a letter under a stated percentage scale.
- Audit a set of letter grades or credit-like weights before comparing your own calculation with an official system.
How to calculate
- The calculator opens with a complete demonstration: Percentage mode, three grades of 67%, 75%, and 72%, and weights of 0.15, 0.35, and 0.50. Its example Excel workbook is validated during initialization and is immediately available.
- Choose Grades type: Percentage, Letters, or Points. Enter Number of grades from 1 to 15. The row controls adjust to the selected mode.
- Replace each demonstration value with your own grade and Weight. A weight is a nonnegative relative factor. Equal weights produce an ordinary arithmetic average; proportional weights such as 15, 35, 50 or 0.15, 0.35, 0.50 produce the same weighted result.
- Read Overall grade, Letter grade, and Total weight. In Points mode, also read Points earned and Points possible. The Grade details table shows each row and its contribution.
- If your course uses a different percentage scale, open Grading scale (thresholds) and edit the minimum percentage for each letter from A+ through D-. Then use Download Excel to export the current valid state.
- Reset clears the demonstration and all grade rows, closes the advanced panel, removes results, and may disable Download Excel until you enter a complete valid state again. Reset keeps the standard grading thresholds as the neutral scale configuration.
Input guide
Grades type is required and selects Percentage, Letters, or Points. Percentage expects decimal numbers from 0 to 100, for example 88.5; Letters expects one listed letter from A+ through F; Points expects nonnegative earned points plus a positive maximum, for example 42 out of 50. Changing the type changes the meaning of the grade column, so do not treat a percentage such as 88 as 88 raw points unless the assignment maximum is 100. Number of grades is required, must be an integer from 1 through 15, and controls how many grade rows participate in the calculation.
Grade 1 through Grade 15 are required for the active rows. In Percentage mode, values must be from 0 through 100 and use a period as the decimal separator; scientific notation and comma-decimal forms are rejected. In Letters mode, choose the exact letter. In Points mode, enter points earned as a decimal number that is at least zero and no greater than that row's maximum. Maximum points 1 through Maximum points 15 appear only in Points mode, are required there, and must be greater than zero. A common mistake is entering a points-earned value larger than its maximum.
Weight 1 through Weight 15 are required nonnegative decimals. A row with weight 0 has no effect on the weighted average; at least one row must have a positive weight. Weights are relative, so 1, 1, 1 and 10, 10, 10 produce the same average. They are not required to sum to 1 or 100. This is why entering 0.15, 0.35, 0.50 is equivalent to 15, 35, 50 for the demonstration.
The advanced fields A+ minimum (%), A minimum (%), A- minimum (%), B+ minimum (%), B minimum (%), B- minimum (%), C+ minimum (%), C minimum (%), C- minimum (%), D+ minimum (%), D minimum (%), and D- minimum (%) are numeric configuration controls from 0 to 100. Their defaults are 97, 93, 90, 87, 83, 80, 77, 73, 70, 67, 63, and 60. They must decrease strictly so each letter owns a distinct interval; F is anything below the D- minimum. These thresholds affect percentage and points letter conversion, but not the GPA-style letter-mode average.
Output guide
Overall grade is the primary result. Percentage and Points modes display a weighted percentage to two decimals; Letters mode displays a weighted grade-point average to two decimals. A higher value means the weighted records are stronger, but the practical meaning depends on your course policy. Letter grade is the corresponding category: in Percentage and Points modes it comes from the current thresholds, while in Letters mode it comes from the standard grade-point bands used by the calculator. Total weight is the exact sum of row weights; it is the denominator of the weighted mean, not a percentage requirement.
The four summary pills repeat Percentage/Letters/Points mode, the active grade count, Total weight, and whether the threshold scale still matches the default Common +/- scale or has become a Custom scale. In Points mode, Points earned and Points possible are simple unweighted totals across active rows, matching the useful score/max view; the weighted percentage can differ from total earned divided by total possible when row weights differ. The Grade details table lists Item, Grade, Weight, Weighted contribution, and Maximum points when applicable. Weighted contribution is each row's numerator contribution before dividing by total weight.
Worked example
The startup example uses 67% with weight 0.15, 75% with weight 0.35, and 72% with weight 0.50. The weighted numerator is 67×0.15 + 75×0.35 + 72×0.50 = 10.05 + 26.25 + 36.00 = 72.30. The weights sum to 1.00, so 72.30 ÷ 1.00 = 72.30%. With the default thresholds, 72.30% is at least the 70% C- minimum but below the 73% C minimum, so the displayed Letter grade is C-. The first-open table, summary pills, and Excel workbook all use these same values.
How weighted grades are interpreted
The core formula is the weighted mean. In percentage mode it is:
In points mode, each row is first converted to a proportion, earned points ÷ maximum points, and that proportion is weighted. In letter mode, each letter is represented by a grade-point value before the same weighted-mean structure is applied. For a university example of multiplying grade points by credits and dividing by total credits, see Duke University's explanation of GPA calculation. Portland State University provides a similar credit-weighted GPA calculation walkthrough.
Default percentage-to-letter thresholds
| Letter | Minimum percentage | Default interval |
|---|---|---|
| A+ | 97% | 97% – 100% |
| A | 93% | 93% – below 97% |
| A- | 90% | 90% – below 93% |
| B+ | 87% | 87% – below 90% |
| B | 83% | 83% – below 87% |
| B- | 80% | 80% – below 83% |
| C+ | 77% | 77% – below 80% |
| C | 73% | 73% – below 77% |
| C- | 70% | 70% – below 73% |
| D+ | 67% | 67% – below 70% |
| D | 63% | 63% – below 67% |
| D- | 60% | 60% – below 63% |
| F | – | Below 60% |
Grading scales are institution-specific. The NCES transcript study notes that grade information can vary considerably among schools, which is why this calculator exposes its percentage thresholds instead of presenting one scale as universal. Always compare the calculator's assumptions with the syllabus or official grading policy that applies to you.