How to use the test grade calculator
- Choose how the test was scored. “Questions wrong” is for tests where every question is worth the same. “Points” is for tests with weighted questions, partial credit or extra credit.
- Enter the numbers. For a 40-question test with 7 wrong, enter 40 and 7. For a test scored out of 95 points where you earned 86, switch to points and enter 86 and 95.
- Check the grading scale. The default is the common 10-point scale: A from 90%, B from 80%, C from 70%, D from 60%. Change the cutoffs to match your syllabus.
In questions mode, a chart lists the score and letter for every possible number wrong, with your row highlighted. It also shows the most questions you could miss and still reach the A and C cutoffs.
How a test grade is calculated
with equal questions: (questions − wrong) ÷ questions × 100
This is the “what percent is A of B” question from basic percentages. 7 wrong out of 40 means 33 correct, and 33 ÷ 40 = 0.825, or 82.5%, a B on the 10-point scale. 3 wrong out of 25 is 22 ÷ 25 = 88%. 86 points out of 95 is 90.53%, just over the A line.
Each question’s value is 100 ÷ the number of questions. On a 25-question test each one is worth 4 points; on a 40-question test, 2.5 points; on a 30-question test, 3.33 points. That is why missing three questions costs more on a short quiz than on a long exam.
Letter grade scales differ
There is no national letter-grade scale. College Board’s BigFuture guide describes one commonly used system in which an A is 90–100, a B is 80–89 and a C is 70–79, and it notes that your school may calculate grades differently; in its table, a D runs from 66 to 69 and anything below 65 is an E or F. Many schools put the D line at 60 instead, and some use a 7-point scale with an A starting at 93.
Plus and minus grades split each band further. One arrangement puts B− at 80, B at 83 and B+ at 87, but the split points vary. Enter your school’s cutoffs for A through D to get the right letter; plus and minus marks can be read off the percentage.
Policies also differ on rounding. Some teachers round 89.5% up to 90%, others don’t. The calculator shows the score to two decimal places and compares it with the cutoffs exactly as entered, so set the A cutoff to 89.5 if your teacher rounds.
A grading chart for teachers
Grading a stack of tests is quicker with a chart that turns “number wrong” straight into a score. Enter the number of questions, and the table lists every row from 0 wrong to all wrong, along with the letter grade on your scale. On a 20-question test, for instance, 3 wrong is 85% and 5 wrong is 75%.
The “most wrong” lines answer the question students ask most often before a test: how many can I miss and still get an A? On a 40-question test with a 90% cutoff, the answer is 4, since 36 of 40 is exactly 90%. On a 30-question test with a 70% cutoff, 9 wrong (21 of 30) still earns a C.
The chart assumes equal-value questions. For a test that mixes multiple-choice questions with longer written answers, total the points for each student and use points mode.
Partial credit and extra credit
When some answers earn part of their points, count wrong answers in points, not questions. A 10-question test worth 10 points each, where a student gets 7 fully right, 2 half right and 1 wrong, has 70 + 10 = 80 points out of 100, or 80%.
Extra credit can push a score above 100%. 52 points on a test out of 50 is 104%. The calculator shows the extra-credit points separately. Whether a course grade can exceed 100% because of it is up to the teacher.
Bonus questions work differently from extra credit in some classes: they are added to the points possible as well as the points earned, which lowers their value. If you aren’t sure which applies, ask before you rely on the figure.
From one test to your course grade
A single test is usually one piece of a weighted course grade. If tests count for 40% of the grade and this is one of four equal tests, it moves your course grade by a tenth of the gap between this score and your other work. The final grade calculator shows the score you need on a final exam to reach a target grade, and it can work out your current grade from category weights.
Points-based courses are simpler: add the test’s points to your running totals of points earned and points possible, and divide.
How common test curves change a score
Teachers sometimes curve a hard test. Two simple methods are easy to check with this calculator:
- Add points to everyone so the top score becomes 100%. If the highest score was 92%, every student gets 8 points added, and an 82.5% becomes 90.5%.
- Square-root curve: the new score is 10 × √(old score). An 82.5% becomes 10 × 9.083 = 90.8%, a 64% becomes 80%, and a 100% stays 100%. Low scores gain more than high ones.
Enter the curved percentage in points mode, out of 100, to see the new letter grade. Whether and how a test is curved is the teacher’s decision.
From a letter grade to GPA points
On the traditional 4.0 scale described by BigFuture, an A is worth 4 points, a B 3, a C 2, a D 1 and an F 0. A single test doesn’t go on a transcript, but the letter it earns tells you which way it is pushing your course grade, and the course grades are what make up your GPA. The weighted GPA and college GPA calculators take it from there.
Tests with sections worth different points
Counting wrong answers can mislead when sections carry different weights. Picture a test with 20 multiple-choice questions at 2 points each and 3 essays at 20 points each, 100 points in all. A student who gets 17 multiple-choice questions right (34 of 40 points) and earns 45 of 60 essay points has 79 points, or 79%. Counting questions instead, 17 right plus partial essays, would give a misleading figure. Points mode handles this correctly.
Sources & assumptions
How this calculator gets its numbers. Full method: our methodology.
- Score = points earned ÷ points possible × 100; with equal questions, (questions − wrong) ÷ questions × 100.
- Letter grades use the cutoffs shown, defaulting to A 90, B 80, C 70, D 60; scores are compared without rounding.
- The most-wrong figure is the largest number of misses that still meets the cutoff.
- Extra credit can produce a score above 100%.
Sources
- College Board, BigFuture, How to Calculate Your GPA on a 4.0 Scale. The 4.0 conversion (A = 4, B = 3, C = 2, D = 1, F = 0), the worked example of three A’s, a B and a C averaging 3.4, the average U.S. high school GPA of 3.0, and the note that colleges may recalculate GPA their own way.
Last reviewed . Your teacher’s syllabus decides the scale, rounding and how this test counts toward the course grade.
Frequently asked questions
How do I calculate my test score?
Divide the points you earned by the points possible and multiply by 100. With equal-value questions, divide the number you got right by the number of questions: 33 right out of 40 is 82.5%.
What percentage is 7 wrong out of 40?
You got 33 right, and 33 ÷ 40 = 82.5%. On a 10-point scale that is a B.
How many questions can I miss and still get an A?
Multiply the number of questions by the A cutoff as a decimal, round up, and subtract from the total. On a 25-question test with a 90% cutoff, you need 22.5, rounded up to 23 right, so you can miss 2.
Is 89.5% an A?
Only if your teacher rounds up. On a strict 90% cutoff, 89.5% is a B+. Set the A cutoff to 89.5 in the calculator if your class rounds.
What is a 70% on a test?
On the common 10-point scale, 70–79% is a C. Some schools use different cutoffs, so check your syllabus.
How do I grade a test with questions worth different points?
Add up the points earned on each question and divide by the total points possible. Use the calculator’s points mode for this.