Scores Out of 51 as Percentages
Every possible score on a 51-question test or assignment, converted to a percentage and letter grade — from 0/51 (0%) all the way to 51/51 (100%). Below the chart you'll find how to do the conversion yourself, the key passing and A-grade thresholds out of 51, and answers to the most common questions.
How to Convert a Score Out of 51 to a Percentage
To convert any score out of 51 to a percentage, divide the score by 51 and multiply by 100:
percent = (score ÷ 51) × 100
example: (46 ÷ 51) × 100 = 90.2%
The resulting percentage is then mapped to a letter grade on the standard 10-point scale. The full table below has already done this for every score out of 51.
Common Scores Out of 51
The score you need out of 51 to hit each key percentage threshold:
- Passing (D, 60%) 31/51 (60.8%) D
- Half marks (50%) 25.5/51 (50%) F
- C grade (70%) 36/51 (70.6%) C
- B grade (80%) 41/51 (80.4%) B
- A grade (90%) 46/51 (90.2%) A
- Perfect (100%) 51/51 (100%) A
In short: you need 31/51 to pass (60%) and 46/51 for an A (90%).
Full Grade Chart — Every Score Out of 51
| Score | Percentage | Letter Grade | Wrong |
|---|---|---|---|
| 0/51 | 0% | F | 51 |
| 1/51 | 2% | F | 50 |
| 2/51 | 3.9% | F | 49 |
| 3/51 | 5.9% | F | 48 |
| 4/51 | 7.8% | F | 47 |
| 5/51 | 9.8% | F | 46 |
| 6/51 | 11.8% | F | 45 |
| 7/51 | 13.7% | F | 44 |
| 8/51 | 15.7% | F | 43 |
| 9/51 | 17.6% | F | 42 |
| 10/51 | 19.6% | F | 41 |
| 11/51 | 21.6% | F | 40 |
| 12/51 | 23.5% | F | 39 |
| 13/51 | 25.5% | F | 38 |
| 14/51 | 27.5% | F | 37 |
| 15/51 | 29.4% | F | 36 |
| 16/51 | 31.4% | F | 35 |
| 17/51 | 33.3% | F | 34 |
| 18/51 | 35.3% | F | 33 |
| 19/51 | 37.3% | F | 32 |
| 20/51 | 39.2% | F | 31 |
| 21/51 | 41.2% | F | 30 |
| 22/51 | 43.1% | F | 29 |
| 23/51 | 45.1% | F | 28 |
| 24/51 | 47.1% | F | 27 |
| 25/51 | 49% | F | 26 |
| 26/51 | 51% | F | 25 |
| 27/51 | 52.9% | F | 24 |
| 28/51 | 54.9% | F | 23 |
| 29/51 | 56.9% | F | 22 |
| 30/51 | 58.8% | F | 21 |
| 31/51 | 60.8% | D | 20 |
| 32/51 | 62.7% | D | 19 |
| 33/51 | 64.7% | D | 18 |
| 34/51 | 66.7% | D | 17 |
| 35/51 | 68.6% | D | 16 |
| 36/51 | 70.6% | C | 15 |
| 37/51 | 72.5% | C | 14 |
| 38/51 | 74.5% | C | 13 |
| 39/51 | 76.5% | C | 12 |
| 40/51 | 78.4% | C | 11 |
| 41/51 | 80.4% | B | 10 |
| 42/51 | 82.4% | B | 9 |
| 43/51 | 84.3% | B | 8 |
| 44/51 | 86.3% | B | 7 |
| 45/51 | 88.2% | B | 6 |
| 46/51 | 90.2% | A | 5 |
| 47/51 | 92.2% | A | 4 |
| 48/51 | 94.1% | A | 3 |
| 49/51 | 96.1% | A | 2 |
| 50/51 | 98% | A | 1 |
| 51/51 | 100% | A | 0 |
Letter Grade Breakdown
Letter grades out of 51 use the standard 10-point scale:
- A — 90% and above (46/51 or higher)
- B — 80% to 89.9% (41/51 or higher)
- C — 70% to 79.9% (36/51 or higher)
- D — 60% to 69.9% (31/51 or higher)
- F — below 60% (under 31/51)
Frequently Asked Questions
What is a passing score out of 51?
On the standard 10-point scale, 60% is the passing threshold (a D). Out of 51, that means you need at least 31 correct to pass — 31/51 works out to 60.8%. Anything below 31/51 falls under 60% and is a failing grade.
How many questions can you get wrong out of 51 and still pass?
You can miss up to 20 questions out of 51 and still pass. Getting 31/51 correct gives you 60.8% (a D, the lowest passing grade). Miss more than 20 and you drop below 60%.
How many can you get wrong out of 51 and still get an A?
To earn an A you need 90% or higher. Out of 51, that means at least 46 correct (46/51 = 90.2%), so you can afford to miss at most 5 questions.
What is half of 51 as a percentage?
Half of 51 is 25.5, and 25.5/51 is exactly 50%. Under the standard 10-point scale that is a failing grade (F), since 50% is below the 60% passing line.
Is a score out of 51 graded on a 10-point scale?
Most US schools use the standard 10-point scale regardless of the denominator: A is 90%+, B is 80%+, C is 70%+, D is 60%+, and anything below 60% is an F. A raw score out of 51 is first converted to a percentage — divide by 51 and multiply by 100 — then mapped to a letter. Your own school's cutoffs may differ, so check your syllabus.
Related Tools
- Test Grade Calculator — grade any 51-question test interactively; enter the number wrong and get your score plus a printable grading scale.
- Percent to Letter Grade converter — turn any percentage into its letter grade on the standard scale.
- GPA Calculator — roll individual course grades and credit hours into a weighted or unweighted GPA.