How to calculate a test grade percentage
The formula: divide the points earned by the points possible and multiply by 100. For 12 out of 14, that is 12 ÷ 14 × 100 = 85.714..., which this calculator prints as 85.71.
When the teacher counts wrong answers instead, take the number wrong away from the total first. With 7 wrong on a 40-question test, 33 correct answers are left, and 33 ÷ 40 × 100 = 82.50. The two routes agree only when each question carries the same weight, which the next part takes up.
Gradebooks express a score the same way. In Blackboard’s guide, a score of 21/30 “appears as 70%”, and PowerSchool’s guide to its student information system speaks of a percentage “of the total points”. Those are the guides’ examples, not a rule for any school.
The figure here is rounded once, half up, to two decimals; your school may round differently. The method holds for a quiz, an exam or any score out of a total.
12 ÷ 14 × 100 = 85.71
When questions are worth different points
Count points, not questions, whenever questions carry different points; subtracting the number wrong works only when every question is worth the same. Take a 20-question test with 15 questions worth 4 points and 5 worth 8, 100 points in all. A student who misses two of the 8-point questions has 84 of 100, or 84.00%. Counted as 2 wrong out of 20, the same paper comes out at 90.00%, six percentage points too high.
On a test like that, read the points earned and the points possible off the paper and use the Points tab, which takes any mix. The number-wrong tab carries a line saying it treats every question as worth the same.
Test grade chart for 14 questions
On a 14-question test worth one point a question, each question is worth about 7.14 percentage points: 12 right is 85.71% and 10 right is 71.43%. The chart below lists every score. The calculator above draws the same chart for any whole-number total up to 200, with a half-point step for tests marked in halves, where 0.5 wrong out of 5 is 90.00%.
| Wrong | Correct | Percentage |
|---|---|---|
| 0 | 14 | 100.00 |
| 1 | 13 | 92.86 |
| 2 | 12 | 85.71 |
| 3 | 11 | 78.57 |
| 4 | 10 | 71.43 |
| 5 | 9 | 64.29 |
| 6 | 8 | 57.14 |
| 7 | 7 | 50.00 |
| 8 | 6 | 42.86 |
| 9 | 5 | 35.71 |
| 10 | 4 | 28.57 |
| 11 | 3 | 21.43 |
| 12 | 2 | 14.29 |
| 13 | 1 | 7.14 |
| 14 | 0 | 0.00 |
Is there a standard grading scale?
No official page read publishes one: the scale is the school’s, the district’s or the teacher’s. Several calculators print a 12-letter table, with A+ at the top, A from 93, B from 83 and D- from 60, as “the standard” US scale. It matches none of the three published below.
The makers set none either. “Without a grading scheme,” Canvas’s guide says, “scores are not measured against any specific standard.” In Blackboard the default schema is “defined by the administrator”, and PowerSchool calls a cut-off “a suggested cutoff for your teachers to use”. George Mason University’s registrar (page last updated 2013) says it “does not dictate a grading scale”.
Is 75 out of 80 an A? It is 93.75%: an A under Howard County’s policy, which rounds it to 94, and an A- on both Canvas tables, whose A starts at 94. Its policy sets middle and high school letter grades, without saying each test is lettered on it.
| Letter | Howard County | Yale’s Canvas page | CU Boulder’s IT page |
|---|---|---|---|
| A | 90-100% | 94 to 100% | 94 to 100% |
| A- | — | 90 to under 94 | 90 to under 94 |
| B+ | — | 87 to under 90 | 87 to under 90 |
| B | 80-89% | 84 to under 87 | 83 to under 87 |
| B- | — | 80 to under 84 | 80 to under 83 |
| C+ | — | 77 to under 80 | 77 to under 80 |
| C | 70-79% | 74 to under 77 | 73 to under 77 |
| C- | — | 70 to under 74 | 70 to under 73 |
| D+ | — | 67 to under 70 | 67 to under 70 |
| D | 60-69% | 64 to under 67 | 63 to under 67 |
| D- | — | 61 to under 64 | 60 to under 63 |
| F or E | E: 59% or lower | F: under 61 | F: under 60 |
No plus or minus on Howard County’s records; it rounds to a whole number first.
One score, three letters
The same score can take a different letter on each published scale, so a letter means nothing until you know whose scale it is. Two things move the rows apart. Howard County rounds to a whole number before it reads the letter, and the two Canvas tables start B, C, D and D- one point apart, so 83.50 and 60.50 land on different letters.
| Score | Percentage | Howard County | Yale’s Canvas table | CU Boulder’s Canvas table |
|---|---|---|---|---|
| 12 of 14 | 85.71 | B | B | B |
| 13 of 15 | 86.67 | B | B | B |
| 10 of 14 | 71.43 | C | C- | C- |
| 27 of 40 | 67.50 | D | D+ | D+ |
| 18 of 20 | 90.00 | A | A- | A- |
| 75 of 80 | 93.75 | A | A- | A- |
| 179 of 200 | 89.50 | A | B+ | B+ |
| 167 of 200 | 83.50 | B | B- | B |
| 121 of 200 | 60.50 | D | F | D- |
| a 75% | 75.00 | C | C | C |
| a 63% | 63.00 | D | D- | D |
Does a test grade round up?
That is your school’s or teacher’s rule, and the pages read differ. Under Howard County’s policy a fractional score is rounded to the nearest whole number, as its own examples show: 89.49% becomes 89, a B on its scale, and 89.50% becomes 90, an A. At UW Bothell’s nursing school (policy revised 2018), rounding is “at the discretion of each faculty member”. Blackboard’s guide says its calculated columns are cut after two decimals for display and are “never rounded up”. Schoology rounds single items to the hundredth place. So 2 of 3 can show as 66.66, 66.67 or 67.
A scale printed in whole-number bands leaves a decimal nowhere to go unless a rounding rule places it: the 12-letter table jumps from 92 to 93 with no word on 92.5.
This calculator prints two decimals, rounded half up. With a scale chosen, a figure that rounding would push across the scale’s line is cut instead, with a note: 35.998 out of 40 is 89.995%, shown as 89.99 under the table on Yale’s Canvas help page but 90.00 with no scale.
Is it a passing grade?
None of the official pages read sets a pass line for anyone but itself, so the answer is your school’s. Under Howard County’s policy, 59% or lower is an E, “Failure”, with no credit for high school credited courses, and 60-69% is a D, “Low level of achievement”. After the policy’s rounding, 59.5% counts as a D. UW Bothell’s nursing school requires at least a 2.0, which its scale puts at 70%, in undergraduate core courses: a course minimum for a degree, not a pass mark for a test.
Take 27 out of 40, which is 67.50%. It is a D under Howard County’s policy, a D+ on both Canvas tables (whose pages call no letter a pass or a fail), and under the 70% that UW Bothell’s nursing school asks for in a core course. None of the three is yours until you know your school’s line. The calculator itself never prints “pass” or “fail”.
A score above the total, and a total of zero
A score above the points possible is a percentage above 100: 45 out of 40 is 112.50%. Whether it counts is the school’s rule. Extra credit, in Canvas’s guide, “is currently not a default option”; one route it describes is points beyond an assignment’s value, taking a 40-point assignment to 45. One district shuts the door; Howard County’s policy says “Extra credit is not offered in grades 6-12”. This calculator prints it above 100 with a note and, on a chosen scale, gives it the top letter: a convention of this calculator, since no scale read goes above 100.
A total of 0 has no percentage: there is nothing to divide by. Canvas’s guide says so of an assignment group with no points possible: “12 cannot be divided by 0.”
What the official pages say about a test score
The gradebook makers and the schools read for this page each speak for themselves, and they differ on the scale, the rounding and extra credit. These are the eleven pages read on October 14, 2026. Each help page describes what its product can be set to do; how your class is set up is your teacher’s choice.
| Source | A score as a percentage | The letter scale | Rounding | Above the total |
|---|---|---|---|---|
| Canvas (Instructure) | — | Without a scheme, “scores are not measured against any specific standard” | — | Not a default option; points above an assignment’s value is one way its guide lists |
| Blackboard (Anthology) | 21/30 “appears as 70%” | The default schema is “defined by the administrator” | Calculated columns shown cut to two decimals, “never rounded up” | — |
| PowerSchool SIS | A cut-off is a percentage “of the total points” | “a suggested cutoff for your teachers to use” | — | — |
| Schoology (PowerSchool) | — | — | Single items rounded to hundredths | — |
| Howard County Public School System | — | A 90-100%, B 80-89%, C 70-79%, D 60-69%, E 59% or lower | To the nearest whole number: 89.49% is 89, 89.50% is 90 | “Extra credit is not offered in grades 6-12” |
| George Mason University | — | “does not dictate a grading scale” (page last updated 2013) | — | — |
| UW Bothell, School of Nursing & Health Studies | Its scale is headed “Percentage of Earned Points” | Its own scale; 2.0 is 70% (revised 2018) | “at the discretion of each faculty member” | — |
What this calculator does not work out
It grades one score on one test. A course grade built from several tests, quizzes and assignments, weighted or in points, is a job for the grade percentage calculator. The score you still need on a final exam to reach a target is the final grade calculator’s question. A GPA from letter grades belongs to the cumulative GPA calculator. Each of those pages works from more than one score; this one stops at the percentage of a single paper, and the letter you choose a scale for.