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Grades · Grading

Rubric Grade Calculator

Score a project from its rubric criteria — with or without weights — to get an overall percentage and letter grade.

CriterionEarnedPossibleWeight %
Sample rubrics — tap to load
Overall grade
85%B

Weights total 100%.

CriterionScoreWeightContribution
Thesis88% (22/25)25%22 pts
Evidence86.67% (26/30)30%26 pts
Organization84% (21/25)25%21 pts
Mechanics80% (16/20)20%16 pts

To grade from a rubric, score each criterion (earned ÷ possible × 100), multiply by its weight, add them up, and divide by the total weight. With Thesis 90% (weight 40) and Evidence 80% (weight 60): overall = (40×90 + 60×80) ÷ 100 = 8,400 ÷ 100 = 84%, a B.

How rubric grading works

A rubric breaks a project into criteria — thesis, evidence, organization, mechanics — each scored out of its own points. There are two ways to combine them. If every criterion carries equal footing, just add all the points earned and divide by all the points possible. If some criteria matter more, give each a weight and the tool takes a weighted average instead.

Leave every weight blank to grade on raw points; fill any weight in to switch to weighted mode. In weighted mode a criterion’s share of your grade comes from its weight, not its point total, so a 10-point criterion weighted 40% moves your grade more than a 30-point criterion weighted 10%.

overall = Σ(weight × (earned ÷ possible × 100)) ÷ Σ(weight)

dividing by the total weight normalizes rubrics whose weights don’t add to 100%

Worked example

Thesis 22/25 (weight 25), Evidence 26/30 (weight 30), Organization 21/25 (weight 25), Mechanics 16/20 (weight 20).

  1. 1
    Score each criterion. 22/25 = 88%, 26/30 ≈ 86.7%, 21/25 = 84%, 16/20 = 80%.
  2. 2
    Weight each score. 25×88 + 30×86.7 + 25×84 + 20×80 = 2,200 + 2,600 + 2,100 + 1,600 = 8,500.
  3. 3
    Divide by total weight. Weights sum to 100, so overall = 8,500 ÷ 100 = 85%.
  4. 4
    Map to a letter. 85% falls in the 80–89% band, so the grade is a B.

Percentage → letter grade

A common US scale. Exact cutoffs vary by instructor and institution — some use plus/minus bands, some round differently, so always check your syllabus.

PercentageLetter
90–100%A
80–89%B
70–79%C
60–69%D
Below 60%F

Reading your result

Weights that don’t total 100. No problem — the calculator divides by the total weight you actually enter, so a rubric weighted 40/30/20 (summing to 90) is normalized to that 90, not forced to 100. The result notes the sum so you can spot a typo.

Points vs. percentages. Enter the points a rubric awards (18 out of 20); the tool converts each criterion to a percentage for you. If your rubric already gives percentages, enter the percentage as “earned” and 100 as “possible”.

Cutoffs vary. The letter shown uses the common scale above. Your instructor may set different thresholds or use plus/minus grades — treat the letter as a guide, not a verdict.

How do weighted rubric criteria work?
Each criterion is first scored as earned ÷ possible × 100, then multiplied by its weight. The tool adds those weighted scores and divides by the total weight, so a criterion’s influence tracks its weight rather than its point total.
What if my rubric uses points, not percentages?
Enter the points directly — earned and possible per criterion. The tool converts each to a percentage before combining. If you leave every weight blank, it simply totals all points earned over all points possible.
What happens if I leave the weight column blank?
With no weights the calculator uses raw points: overall = total earned ÷ total possible × 100. Fill in any weight and it switches to a weighted average across the criteria that have a weight.
Do the weights have to add up to 100?
No. The result is normalized by the total weight you enter, so weights of 40, 30 and 20 (summing to 90) still give a correct weighted average. The tool notes the sum so an accidental typo is easy to catch.
How is the letter grade decided?
From the overall percentage using a common US scale — A ≥ 90, B ≥ 80, C ≥ 70, D ≥ 60, otherwise F. Exact cutoffs vary by instructor and institution, so check your syllabus.
Can I mix weighted and unweighted criteria?
If at least one criterion has a weight, the tool runs in weighted mode and only the criteria that carry a weight count toward the grade. To grade everything by raw points instead, clear all the weights.
How do I handle a criterion scored zero out of zero?
A criterion with zero points possible is skipped to avoid dividing by zero. Give it a real points-possible value, or remove the row, so it contributes to the grade.