I am excited to assign more writing now that I can give them specific and objective feedback more quickly. I may even postpone my retirement because of your product!
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85%B
Set the test size once, then change the number wrong for each student.
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Step by step
How to grade a quiz
To grade a quiz, divide the number of correct answers by the total number of questions, then multiply by 100.
- Step 1
Count the correct answers
Subtract the number the student missed from the total number of questions on the quiz.
- Step 2
Divide by the total
Divide the correct answers by the total number of quiz questions.
- Step 3
Multiply by 100
Multiply the result by 100 for the percentage, then match it to a letter grade. 13 correct out of 15 is 87%, a B.
Reference chart
Quiz grade by number of questions
The score for each number wrong across common quiz sizes. Change the number of questions in the calculator above for any size.
| Number wrong | 5 questions | 10 questions | 15 questions | 20 questions | 25 questions |
|---|---|---|---|---|---|
| 0 | 100% | 100% | 100% | 100% | 100% |
| 1 | 80% | 90% | 93% | 95% | 96% |
| 2 | 60% | 80% | 87% | 90% | 92% |
| 3 | 40% | 70% | 80% | 85% | 88% |
| 4 | 20% | 60% | 73% | 80% | 84% |
| 5 | 0% | 50% | 67% | 75% | 80% |
On the standard scale, 90% and up is an A, 80% a B, 70% a C, and 60% a D. Enter any quiz size in the calculator above for the exact letter grade. Grading a full test or worksheet instead? The easy grader runs the same math for any assignment.
Question types
Multiple-choice and short-answer questions
A quiz usually mixes two kinds of questions, and they are graded in different ways.
Multiple-choice and objective
Every question has one correct answer, so the score is countable. Enter the totals in the calculator above and the percentage is done in a second.
Short-answer and open response
There is no single answer key. These need a rubric, partial credit, and your judgment, which is the part CoGrader handles below.
Grade the written answers
A percentage is the easy part. The questions worth grading are the short answers and open responses, and a calculator cannot score those. CoGrader reads each response, drafts a first-pass score aligned to your rubric, and adds comments that explain it, so you start with a thoughtful draft and keep the final say on every grade.
- Rubric-aligned feedback on every short answer and open response.
- A class set of quizzes graded in minutes, not a weekend.
- You review every score and keep the final say.
Why teachers use CoGrader
Meet your grading tool
CoGrader helps with your whole grading workload, drafting rubric-aligned feedback while you keep the final say on every grade.
Faster feedback
Shorten the loop to a day or two instead of weeks, so students act on comments while the quiz is still fresh.
Save time
Return meaningful, specific feedback while saving up to 80% of your grading time.
Grade more writing
When feedback is fast, you can add the short-answer questions you have been leaving off the quiz.
Consistent grading
Rubric-based scoring keeps results steady across sections and co-teachers.
Class insights
See where the class missed the same question and plan the reteach.
Works with your LMS
Import quizzes from Google Classroom, Canvas, or Schoology, and send reviewed grades and feedback back.
See CoGrader at work
CoGrader applies your rubric to a class set of responses and drafts rubric-aligned feedback for every student.
You get the first draft, so you can focus on the comments that actually move the needle.
Integrate with your LMS
Import a set of quizzes, grade the open responses against your rubric, and send grades and feedback back, all from inside the tools your school already uses.
Trusted by K-12 teachers nationwide
Teachers across the country use CoGrader to grade against a rubric and give every student timely, specific feedback.
I am absolutely blown away by CoGrader. It has been excellent for pre-scoring essays and providing students with comprehensive, usable feedback.
What usually takes me days (and way too many hours of off-contract time), took me mere hours. I plan on hosting a PD for my staff in the next few weeks.
Co-workers, students and I have compared results from CoGrader with a variety of other AI scoring for AP essays, and yours is BY FAR the most accurate.
Helping teachers GRADE but more importantly helping GIVE QUALITY FEEDBACK, and putting the power of great feedback into the hands of kids so they have AGENCY to improve.
Teachers will be motivated to assign more writing. It allows teachers to personalize student feedback quickly, leaving more time for targeted instruction.
I almost cried when I used it. It was as if someone handed me my weekends back on a silver platter.
THANKS. CoGrader is BY FAR the most accurate AI scoring for AP essays I have used, with the best feedback.
I am excited to assign more writing now that I can give them specific and objective feedback more quickly. I may even postpone my retirement because of your product!
I am absolutely blown away by CoGrader. It has been excellent for pre-scoring essays and providing students with comprehensive, usable feedback.
What usually takes me days (and way too many hours of off-contract time), took me mere hours. I plan on hosting a PD for my staff in the next few weeks.
Co-workers, students and I have compared results from CoGrader with a variety of other AI scoring for AP essays, and yours is BY FAR the most accurate.
Helping teachers GRADE but more importantly helping GIVE QUALITY FEEDBACK, and putting the power of great feedback into the hands of kids so they have AGENCY to improve.
Teachers will be motivated to assign more writing. It allows teachers to personalize student feedback quickly, leaving more time for targeted instruction.
I almost cried when I used it. It was as if someone handed me my weekends back on a silver platter.
THANKS. CoGrader is BY FAR the most accurate AI scoring for AP essays I have used, with the best feedback.
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Frequently Asked Questions
Grading a quiz, answered.
What is a quiz grader?
A quiz grader is a free tool that turns a raw quiz score into a percentage and letter grade. Enter the number of questions and how many the student missed, and the grade appears as you type. For the written questions on a quiz, CoGrader grades each response to your rubric and leaves you the final say.
What grade is 7 wrong out of 40?
That is 33 correct out of 40, which is 82.5%, a B on the standard scale. Divide the correct answers by the total and multiply by 100. Enter 40 questions and 7 wrong in the calculator above to check it.
Is 27 out of 40 a passing grade?
Yes. 27 out of 40 is 67.5%, a D, which passes on the standard scale where 60% and above is passing. Districts that set higher cutoffs can change the letter-grade thresholds to match.
How do I grade a quiz with a different number of questions?
Enter the total in the first field. The calculator handles any quiz size, from a 5-question exit ticket to a 50-item unit test, and updates the score and letter as you change the number wrong.
Is this quiz grader free? Do I need to sign up?
Yes, it is free, and there is no account to create. The calculator runs in your browser, so nothing you type is saved or sent anywhere. Open it on a phone or a laptop and start grading.
Can CoGrader grade the written or short-answer questions, not just multiple-choice?
Yes. This calculator scores the countable questions. For short answers and open responses, CoGrader grades each one to your rubric, suggests a score with comments that explain it, and you stay in control of the final grade. See AI grading.
Does it support half points or a custom grading scale?
Yes. You can enter half points for partial credit, and you can adjust the letter-grade cutoffs to match your district scale. The standard A-F scale is the default, and the thresholds are editable.
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