Grade Percentage Calculator

How the grade percentage calculator works

Enter two numbers in the grade percentage calculator above: the points you earned and the points possible. That is the whole job. The tool divides one by the other, multiplies by 100, and shows your percentage, letter grade, and GPA while you type. There is no Calculate button because you should not need one. The preloaded example, 18 out of 20, reads 90%, an A on the simple scale.

A few shortcuts are built in. If your score is already written as a fraction, paste the whole thing into the first field and “18/20” splits itself across both boxes. If you only know what you lost, switch to points missed and type that instead; the calculator works out the points earned for you. There is also a target helper for the reverse question. Tell it you want 92% on a 50-point exam and it answers 46 out of 50.

The plus/minus toggle swaps between a simple A-F scale and the 13-band scale with grades like A− and B+. Reset clears the fields, and Copy puts the result line on your clipboard. Students use it for any test, quiz, homework, essay, or project scored in points; teachers use it to mark a whole stack of papers, which gets its own section below.

Grade percentage formula

A grade percentage is points earned divided by points possible, multiplied by 100.

One line, and it covers every points-based score from a five-point vocabulary quiz to a 600-point semester. Your percent grade is just your raw score rewritten as a fraction of 100, which is why any “X out of Y” converts so cleanly.

Here it is with real numbers. You scored 45 out of 50 on a test. Divide: 45 ÷ 50 = 0.90. Multiply: 0.90 × 100 = 90%. On the simple scale that is an A, and on a plus/minus scale it is an A−.

How to calculate a grade percentage by hand

No calculator handy? The conversion takes four steps and about thirty seconds:

1. Find the points possible. Check the top of the test or the gradebook column. A 25-question quiz worth one point per question has 25 points possible.
2. Add up the points you earned. Count partial credit exactly as your teacher wrote it, half points included. Say your marked answers add up to 22.
3. Divide earned by possible. 22 ÷ 25 = 0.88. This decimal is your grade as a proportion.
4. Multiply by 100. 0.88 × 100 = 88%, a B+ on a plus/minus scale and a plain B on the simple one.

The order never changes: possible, earned, divide, multiply. If your result comes out above 100 and you had no extra credit, the usual culprit is swapped numbers in step 3.

Percentage to letter grade chart

Once you have the percentage, this chart converts it to a letter grade and grade points. It is the plus/minus scale most US high schools and colleges publish, and the same one behind the calculator’s toggle.

On the simple scale, A = 90-100, B = 80-89, C = 70-79, D = 60-69, and F = below 60. Many teachers grade with the simple version and skip plus and minus grades entirely, which is why the calculator defaults to it.

One warning before you trust any chart, including this one: grade boundaries vary by school, college, and university. Some start an A at 94, some set the passing grade at 65, and a few skip letter grades altogether. Your syllabus is the final word, so check it whenever a score sits near a cutoff.

Common test scores as percentages and letter grades

The same handful of scores comes up again and again in classrooms, so here is a quick test grade percentage chart of the most common ones, converted on both scales. Only one score refuses to divide evenly; 55/60 is shown rounded to one decimal.

Notice how many different scores collapse to 90%: 9/10, 18/20, 27/30, and 45/50 are all the same grade. The ratio is what matters, never the size of the test. For any score you do not see here, type it into the calculator above and read the result line.

Worked examples

Four examples, four different situations. Each one is the same formula wearing a different outfit.

• A standard course total. Your gradebook shows 510 points earned out of 600 points possible across the semester’s homework, quizzes, and midterm. 510 ÷ 600 = 0.85, so your overall grade is 85%, a B on either scale. This is how you check a whole class grade rather than one test: total everything earned, total everything possible, divide once.
• Decimals and partial credit. An essay comes back marked 37.5 out of 40. The math does not care about the half point: 37.5 ÷ 40 = 0.9375, which is 93.75%, an A. Enter decimals in the calculator exactly as they appear on the paper.
• Extra credit over 100%. You earned 52 out of 50 thanks to a two-point bonus question. 52 ÷ 50 = 1.04, so your score is 104%. The calculator flags it as extra credit rather than treating it as an error. Whether the gradebook caps it at 100% is your teacher’s call.
• The reverse question. Your final exam is worth 60 points and you want 90%. Multiply instead of divide: 0.90 × 60 = 54 points. Miss more than 6 points and you fall short. The target helper in the calculator runs this for any percentage and any point total.

Rounding, extra credit, and edge cases

Is 89.5% an A−? Only if your teacher rounds. The A− band starts at 90, and 89.5 sits below it, so by the raw cutoff it is a B+. Plenty of teachers round to the nearest whole number at the end of the term, which would carry 89.5 up to 90, and plenty do not. Nothing in the math decides this; the syllabus does. If yours is silent on rounding, ask before the final, not after.

A few more edges worth knowing:

• Partial credit and decimals change nothing. 42.5 out of 50 divides exactly like 42 out of 50, just to 85% instead of 84%.
• Scores above 100% are legitimate when extra credit is in play. Report them as calculated unless your gradebook caps grades at 100%.
• Curved grades come after the percentage. Work out your raw percent first, then add whatever curve your professor announces.
• “Marks” means the same thing. If your school talks about marks scored out of maximum marks, the formula is identical: divide, then multiply by 100.

And one disambiguation, because the words look alike: a percentage compares your points to the points possible, while a percentile compares you to other people. Scoring in the 90th percentile means you beat 90% of test takers; it says nothing about how many answers you got right.

For teachers: marking a stack of papers

Grading forty quizzes with the same points possible? Enter the total once and leave it alone. Then type each student’s earned points into the first field, read the percentage and letter, record it, and move to the next paper. The result updates on every keystroke, so the rhythm stays fast. The Copy button helps if you keep a digital markbook open in the next tab.

For work scored with a rubric, add up the rubric points first and enter the sum; the calculator accepts decimals if your rubric awards half points. And keep the common-scores chart above within reach. When a quiz is out of 20 or 25, most of the class will land on a row you can read straight off it.

If you grade by counting questions wrong instead of adding points earned (the EZ-grader workflow), use our test grade calculator instead. You give it the number of questions and the number wrong, and it builds the whole grading chart for that test length.

Need a different grade calculator?

This page does one conversion: points earned out of points possible into a percentage and letter. If your problem is shaped differently, you want a different tool, because the wrong one gives a confidently wrong answer.

When your syllabus weights categories, say tests at 50% and homework at 20%, a plain percentage ignores the weighting; that is a job for a weighted grade calculator. When you have several separate scores and want the mean of the whole set, you need a grade average calculator, which adds the scores and divides by the count. And when you are counting questions wrong rather than points earned, the test grade calculator linked in the teachers’ section above is the right fit.