What grade is 3 wrong out of 20?

3 wrong answers leaves 17 correct, which is 85.0%. That is a B on the standard A–F scale and a B on the plus/minus scale.

Can I give partial credit on a 20-question test?

Yes. On a 20-question test, turn on half points in the Quick Grade calculator and a half-credit answer counts as 2.5% instead of 5%. The chart on this page uses whole questions only.

20 Questions

20-Question Grading Scale

Each question on a 20-question test is worth 5%. On the common 90/80/70/60 scale you can miss up to 2 questions for an A, up to 4 questions for a B, up to 6 questions for a C, up to 8 questions for a D. The chart below shows the percentage and letter grade for every number of wrong answers from 0 to 20.

Custom cutoffs or another test size

Score chart for 20 questions (standard A–F)
Wrong	Correct	Percent	Grade
0	20	100.0%	A
1	19	95.0%	A
2	18	90.0%	A
3	17	85.0%	B
4	16	80.0%	B
5	15	75.0%	C
6	14	70.0%	C
7	13	65.0%	D
8	12	60.0%	D
9	11	55.0%	F
10	10	50.0%	F
11	9	45.0%	F
12	8	40.0%	F
13	7	35.0%	F
14	6	30.0%	F
15	5	25.0%	F
16	4	20.0%	F
17	3	15.0%	F
18	2	10.0%	F
19	1	5.0%	F
20	0	0.0%	F

How a 20-question test is scored

Divide the number of correct answers by 20 and multiply by 100. With 20 questions worth the same amount, each one is 5% of the grade. A 20-question test is a common size for unit quizzes and chapter tests. One missed question costs 5 points, so a single slip rarely decides the letter on its own but two or three often do.

On the common 90/80/70/60 scale you can miss up to 2 questions for an A, up to 4 questions for a B, up to 6 questions for a C, up to 8 questions for a D. Anything below the D line is an F.

Quick reference for 20 questions

These scores come from the same chart you see in the tool above.

0 wrong answers (20 correct) = 100.0%, grade A
1 wrong answer (19 correct) = 95.0%, grade A
2 wrong answers (18 correct) = 90.0%, grade A
3 wrong answers (17 correct) = 85.0%, grade B
4 wrong answers (16 correct) = 80.0%, grade B
6 wrong answers (14 correct) = 70.0%, grade C
8 wrong answers (12 correct) = 60.0%, grade D

Rounding and partial credit on 20 questions

Because 20 divides 100 evenly, every score is a whole percentage: no rounding is needed.

Half points are possible too: one half-credit answer is worth 2.5%.

Worked example: 2 wrong on a 20-question test

A student misses 2 of 20 questions.

Correct answers: 18 of 20
Percentage: 90.0%
Standard A–F: A
Plus/minus: A-

(20 − 2) ÷ 20 × 100 = 90%, so the grade is 90.0% (A).

Grading & Weighting FAQs

Grade Calculator & Scoring FAQs

Clear, mathematically verified answers to common questions about weighted grade averages, grading scales, and final exam target scores.

Each question is worth 100 ÷ 20 = 5% when every question has the same weight. Missing one question leaves 95%, and each further miss lowers the score by another 5 points.

On a 20-question test with the common 90/80/70/60 scale you can miss up to 2 questions for an A. For the other letters you can miss up to 4 questions for a B, up to 6 questions for a C, up to 8 questions for a D. Your teacher’s scale may use different cutoffs, so check the syllabus.

Interactive Tools Available

Test a hypothetical score with our Target Grade Simulator above!