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.
50,000+ Teachers trust CoGrader
1,000+ Schools across all 50 states
2M+ Essays graded with AI
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Used at 1000+ schools
Step by step
How to calculate a grade percentage
To calculate a grade percentage, 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.
- Step 2
Divide by the total
Divide the number of correct answers by the total number of questions.
- Step 3
Multiply by 100
Multiply the result by 100 to get the percentage, then match it to a letter grade. 17 correct out of 20 is 85%, a B.
Reference chart
The grading chart
Here is the score for every number wrong on a 20-question test. Change the number of questions in the calculator above to build the chart for any test size.
- 0 wrong 100% A
- 1 wrong 95% A
- 2 wrong 90% A
- 3 wrong 85% B
- 4 wrong 80% B
- 5 wrong 75% C
- 6 wrong 70% C
- 7 wrong 65% D
- 8 wrong 60% D
- 9 wrong 55% F
- 10 wrong 50% F
A grade calculator is perfect for a quiz with a countable score. For essays and open responses, a rubric does the scoring, which is where CoGrader comes in below.
Grade essays with CoGrader
If you're a teacher with stacks of essays to grade each month, a simple grade calculator isn't enough. CoGrader reviews each essay using your rubric, generates a first-pass score, and provides clear, specific feedback for every student, so you're starting with a thoughtful draft, not a blank page.
- Specific, rubric-aligned feedback on every essay.
- A class set 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 writing workload, drafting rubric-aligned feedback while you keep the final say on every grade.
Faster feedback
Shorten the feedback loop to a day or two instead of weeks, so students stay engaged and improve faster.
Save time
Give students quality, individualized feedback while saving up to 80% of your grading time.
Grade more writing
When feedback is fast, you can assign the essays and short answers you have been putting off.
Consistent grading
Minimize human bias with rubric-based grading that stays consistent across classes and co-teachers.
Class insights
Get a data-driven x-ray of your class's performance to spot gaps and plan your next lesson.
Works with your LMS
Import 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 essays 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 essays, grade them 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 essays 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
Grade percentages and letter grades, answered.
What grade is 8 out of 10?
8 out of 10 is 80%, which is a B on the standard scale. Take the score, divide it by the number of questions, and multiply by 100. Enter any score in the calculator above to convert it the same way.
What is an easy grader, or EZ grader?
It is a grade calculator that turns a raw score into a percentage and letter grade. It replaces the sliding cardboard EZ Grader wheel that sat on teacher desks for decades. You enter the number of questions and the number missed, and it shows the grade the moment you type.
Is this easy grader free? Do I need to sign up?
Yes, it is free, and you do not need an account. 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.
How do I grade a test out of any number of questions?
Enter the total number of questions in the first field. The calculator handles any test size, from a 5-question exit ticket to a 100-item final, and updates the score and letter as you change the number wrong.
Does the easy grader 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, but plenty of schools set their own thresholds, so the scale is editable.
Can CoGrader grade essays and open responses, not just multiple-choice?
Yes. This calculator handles quizzes and tests with a countable score. For essays and open responses, CoGrader reads each one against your rubric, returns a first-pass score with rubric-aligned comments, and leaves you the final say on every grade. See the AI Essay Grader.
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