Test Grade Calculator

Enter the number of questions and how many were missed to get the percentage score, letter grade and points off — the fast way teachers grade a stack of papers.

Grading is really just one division: the number correct divided by the total, turned into a percentage. This calculator does that instantly and maps the result to a letter grade, so you can mark a test in seconds whether you're counting the questions students got wrong or the ones they got right.

How to calculate a test grade

Divide the number of correct answers by the total number of questions, then multiply by 100 for a percentage. If you're counting mistakes instead, subtract them from the total first.

Percentage = (Correct ÷ Total) × 100
Correct = Total − Number wrong
InputMeaning
Total questionsHow many questions or points the test is out of
Number wrongQuestions missed (the classic red-pen count)
CorrectTotal minus wrong — the score numerator

Percentage to letter grade

Letter grades vary by school, but this is the most common US plus/minus scale. Enter your score above to see where it lands; the chart below shows the full mapping.

LetterPercentage
A+ / A / A−97–100 / 93–96 / 90–92
B+ / B / B−87–89 / 83–86 / 80–82
C+ / C / C−77–79 / 73–76 / 70–72
D+ / D / D−67–69 / 63–66 / 60–62
FBelow 60

Worked example

A 50-question test with 5 wrong:

Correct = 50 − 545
Percentage = (45 ÷ 50) × 10090%
Letter gradeA−

Grading tips

For partial credit, count points rather than whole questions — enter the total points possible and the points lost. If different questions are worth different amounts, our weighted tools handle that better; this calculator assumes every question counts equally. When you need to know what a student must score on a remaining test or final to reach a target, use the final grade calculator instead.

Frequently asked questions

What is an EZ grader?
An EZ grader is a quick reference (originally a paper slider) that turns the number of questions wrong into a percentage. This calculator does the same thing digitally for any number of questions.
How do I grade a test out of an odd number of questions?
Just enter the real total — 37, 42, whatever it is. The calculator divides correctly for any number, so you don't need to scale to 100.
Can I count points instead of questions?
Yes. Enter total points as the "total" and points lost as "number wrong". The percentage works the same way.
Are the letter grade cutoffs universal?
No — schools set their own. This uses the common US plus/minus scale. Check your school's grading policy if it differs.

Related calculators

Assumes every question is worth the same. Letter-grade cutoffs follow the common US plus/minus scale and may differ at your school.
Written by the CalcPine team · Reviewed for accuracy · Last updated 11 July 2026 · Method: correct ÷ total × 100.