"X out of Y" becomes a grade in two steps: divide X by Y and multiply by 100 to get the percentage, then match that percentage to your grading scale. On the standard US scale, 90–100% is an A, 80–89% a B, 70–79% a C, 60–69% a D, and below 60% an F. Example: 45 out of 60 is 75%, a C.
How to turn any X out of Y score into a grade
Divide the points you earned by the points available, then multiply by 100. That single calculation works for a 10-question quiz, an 80-point exam, or a 5-mark homework check, because every one of them is really asking what fraction of the available credit you kept. The result is a percentage; the letter grade comes from reading that percentage off your grading scale.
Take 45 out of 60: 45 ÷ 60 = 0.75, and 0.75 × 100 = 75%. On the standard scale that is a C. Take 33 out of 40: 33 ÷ 40 = 0.825, so 82.5%, a B−. The arithmetic never changes; only the two numbers you start with do. The step-by-step percentage method shows every stage worked out.
- Divide the score you got by the total possible score.
- Multiply by 100 to turn the decimal into a percentage.
- Match the percentage to your grading scale to get the letter grade.
Mental-math shortcuts by denominator
When the test total is a round number, you rarely need to divide at all. Each question on an N-question test is worth 100 ÷ N percent, so a score out of 20 is worth 5% per question, a score out of 25 is worth 4% per question, and a score out of 50 is worth 2% per question. Multiply your raw score by that per-question value and you have the percentage.
These shortcuts assume every question is worth the same. If the assignment mixes one-point questions with a ten-point essay, skip the shortcut and add up actual points instead.
| Score is out of | Multiply the score by | Example |
|---|---|---|
| 5 | 20 | 4 out of 5 → 80% |
| 10 | 10 | 7 out of 10 → 70% |
| 20 | 5 | 17 out of 20 → 85% |
| 25 | 4 | 22 out of 25 → 88% |
| 50 | 2 | 47 out of 50 → 94% |
| 100 | 1 | 83 out of 100 → 83% |
| Any other total | Divide, then × 100 | 45 out of 60 → 0.75 → 75% |
Score-to-grade conversion chart
The table below shows the lowest raw score that still earns each letter grade on the standard US scale, for the six test totals people ask about most. Find your out-of total in the left column, then read across: if your score is at least the number shown, you have that letter or better.
A few rows need rounding: 90% of 25 is 22.5, so 23 correct is the first score that reaches an A, and 70% of 25 is 17.5, so you need 18 for a C. For a test total that is not in this table, use the divide-and-multiply method above, or open the grading scale for your exact question count for a full row-by-row breakdown.
| Out of | A (90%+) | B (80%+) | C (70%+) | D (60%+) | F (below 60%) |
|---|---|---|---|---|---|
| 10 | 9 | 8 | 7 | 6 | 5 or fewer |
| 20 | 18 | 16 | 14 | 12 | 11 or fewer |
| 25 | 23 | 20 | 18 | 15 | 14 or fewer |
| 40 | 36 | 32 | 28 | 24 | 23 or fewer |
| 50 | 45 | 40 | 35 | 30 | 29 or fewer |
| 100 | 90 | 80 | 70 | 60 | 59 or fewer |
What letter grade does each percentage get?
Once you have the percentage, the letter comes from your grading scale. The standard US scale splits the range into five bands, and most schools add plus and minus steps inside each band.
The percentage a score produces never changes, but the letter it earns can. Some schools set a straight A at 93% rather than 90%, some run stricter or looser cutoffs, and a curve or a rounding rule can move a borderline score up a step. Always check the scale printed on your syllabus, and see what letter grade each percentage earns for the plus/minus bands.
| Percentage | Letter | GPA value |
|---|---|---|
| 90–100% | A | 4.0 (A− 3.7, A+ 4.0) |
| 80–89% | B | 3.0 (B− 2.7, B+ 3.3) |
| 70–79% | C | 2.0 (C− 1.7, C+ 2.3) |
| 60–69% | D | 1.0 (D− 0.7, D+ 1.3) |
| Below 60% | F | 0.0 |
Is X out of Y a passing grade?
A score passes when its percentage reaches your course's minimum, which is 60% — a D− — in most US high schools. Many colleges set the bar higher and require a C, or 70%, for a course to count toward a major or a graduation requirement. Below the cutoff, the score is an F and earns 0.0 grade points.
Here are the four scores people ask about most. 27 out of 40 is 67.5%, a D+, which passes where 60% is the cutoff and fails where a C is required. 7 wrong out of 40 leaves 33 correct, which is 82.5%, a comfortable B−. 75 out of 80 is 93.75%, an A. And 65% is a D — it passes at most high schools and fails any course with a 70% minimum. Read what counts as a passing grade for the high-school and college rules, and how many questions you can miss to clear a cutoff.
When X out of Y doesn't convert this simply
The divide-and-multiply method assumes two things: every question is worth the same, and the score is the whole grade. If a test has fifteen one-point questions and one ten-point essay, missing the essay costs far more than missing several small questions, so you have to add earned points and divide by total points rather than counting questions. A rubric score works the same way, and so does partial credit: half a mark on a 20-point task is 72.5%, not a whole-question value.
The second trap is treating one score as the course grade. A single quiz is usually a slice of a weighted category — homework 20%, tests 50%, and so on — so a 75% on one quiz moves your course grade by only a fraction of that. Use a gradebook calculator for weighted categories and a points-based calculator for courses graded on total points, and see how much one assignment is worth for the real effect of a single score. A curve is the last exception: it re-scales the whole class after grading, so the raw percentage is only the starting point.
Frequently Asked Questions
What grade is 15 out of 20?+
15 out of 20 is 75%, which is a C on the standard US scale. A few schools that use tighter plus/minus bands count 75% as a C+, so check your syllabus. The GPA value for a C is 2.0.
Is 27 out of 40 a passing grade?+
27 out of 40 is 67.5%, a D+. It passes at schools where 60% is the minimum passing grade, and it fails in any course that requires a C (70%) to earn credit. It also pulls your GPA down toward 1.3.
What grade is 7 wrong out of 40?+
Seven wrong out of 40 means 33 correct. 33 ÷ 40 is 82.5%, a B− on the standard scale. On a 40-question test each question is worth 2.5%, so each additional wrong answer drops the score by 2.5 points.
Is 75 out of 80 an A?+
Yes. 75 ÷ 80 is 93.75%, which is an A on the standard scale and still an A even at schools that set the straight-A line at 93%. You would need to lose about eleven points on an 80-point test before the grade slips to a B.
What percentage do you need to get an A?+
90% on the standard US scale. Some schools raise the line to 92% or 93% for a straight A and use 90–92% for an A−. The exact number is on your course syllabus.
Is 65 percent a passing grade?+
Usually. 65% is a D on the standard scale, which passes in most US high schools. It does not pass a course that sets a C (70%) as the minimum for credit, which is common in college major requirements.
What grade is 45 out of 60?+
45 out of 60 is exactly 75%, a C. Each question on a 60-point test is worth about 1.67%, so 46 out of 60 would be 76.7% and 44 would be 73.3% — still all inside the C band.
Does the letter grade for a score ever change?+
The percentage does not, but the letter can. Different schools set different cutoffs, a curve re-scales the class after grading, and a rounding rule can lift a 79.5% to a B−. The same 79% can be a C+ in one class and a B− in another.
Is a lower "out of" number better or worse?+
Neither — the denominator does not change the percentage. But each question is worth more on a shorter test, so one wrong answer on a 10-question quiz costs 10 points while one wrong answer on a 100-question exam costs only 1. Short tests are less forgiving of a single mistake.
How do I find the score I need for a B?+
Multiply the total by 0.80 and round up to the next whole question. On a 30-question test, 30 × 0.80 = 24, so you need 24 correct for a B. For a straight B− the multiplier is 0.80; for a solid B use 0.83.
What if my questions aren't all worth the same?+
Add up the points you earned and divide by the total points possible, then multiply by 100 — do not count questions. A gradebook calculator or points-based calculator handles this, and it is the correct method for any rubric-scored or mixed-weight assignment.
What grade is 16 out of 20?+
16 out of 20 is 80%, a B− — the bottom of the B band. One more correct answer, 17 out of 20, is 85%, a solid B. One fewer, 15 out of 20, drops to 75% and a C.
Muhammd Salman
I build and maintain Grade Calculator independently. Every worked example on this site is checked against the underlying formula, with notes on where school or instructor policy can change the result. More about this site →