About the Marks Percentage Calculator
Turn the marks you scored into a percentage, for a single test or for several subjects at once, and optionally see the letter grade on a published scale. Enter your marks and the maximum possible marks; the percentage updates as you type.
For several subjects the overall percentage is total marks ÷ total maximum, which is how most report cards work. It is not the same as averaging the subject percentages when the subjects have different maximums, and the calculator shows both numbers so you can see the difference.
How it works
The percentage is the share of the maximum you scored, multiplied by 100. The calculation is exact and is rounded only for display, to two decimal places, rounding halves up (78.335 becomes 78.34).
Percentage = marks obtained ÷ maximum marks × 100 Overall (several subjects) = (sum of marks obtained) ÷ (sum of maximum marks) × 100
If you choose a letter-grade scale, the grade is decided from the unrounded percentage. A score of 89.99% is a B on a scale where A starts at 90%, even though it might look like 90 after rounding.
Assumptions and limits
- Letter grades use the US 10-point scale defined in Florida Statutes §1003.437 (A 90–100, B 80–89, C 70–79, D 60–69, F 0–59). Your school, board or university may use a different scale; choose "No letter grade" if it does.
- Marks above the maximum (bonus marks) are allowed and give a result above 100%, with a warning.
- Use a dot for decimals (37.5). Commas and thousands separators are not accepted.
Worked examples
One test: 455 out of 500
455 ÷ 500 = 0.91, so the percentage is 91%. On the US 10-point scale that is an A.
455 ÷ 500 × 100 = 91% → A (90–100)
A score that doesn't divide evenly: 47 out of 60
47 ÷ 60 = 0.78333…, so the percentage is 78.33% after rounding to two decimals, a C on the 10-point scale.
47 ÷ 60 × 100 = 78.333…% → 78.33% → C (70–79)
Two subjects with different maximums
45 out of 50 (90%) and 80 out of 100 (80%) give 125 out of 150 in total, which is 83.33%. Averaging the two percentages would give 85%, which overstates the result because the second subject is worth twice as many marks.
(45 + 80) ÷ (50 + 100) × 100 = 125 ÷ 150 × 100 = 83.33%
US 10-point grading scale (Florida Statutes §1003.437)
Many US schools use this scale, but cut-offs and plus/minus grades vary. Always check your own school's policy.
| Letter | Percentage | Grade points | Meaning |
|---|---|---|---|
| A | 90–100 | 4 | Outstanding progress |
| B | 80–89 | 3 | Above average progress |
| C | 70–79 | 2 | Average progress |
| D | 60–69 | 1 | Lowest acceptable progress |
| F | 0–59 | 0 | Failure |
How to use the Marks Percentage Calculator
- Choose one test or several subjects. Use "Several subjects" for a report card or a term total.
- Enter marks obtained and maximum marks. Decimals like 37.5 are fine; leave out commas.
- Read the percentage and, if you want, the letter grade. Pick a grading scale or "No letter grade". The working shows exactly how the number was found.
Frequently asked questions
How do I calculate my percentage from marks?
Divide the marks you obtained by the maximum marks and multiply by 100. For example, 455 out of 500 is 455 ÷ 500 × 100 = 91%. The calculator does this exactly and rounds the displayed result to two decimal places.
Why is my overall percentage different from the average of my subjects?
The overall percentage weights each subject by its maximum marks: it is total obtained ÷ total maximum. A plain average of subject percentages treats a 50-mark quiz and a 100-mark exam as equally important, so the two numbers differ whenever the maximums differ.
Is 89.5% rounded up to an A?
Not here. The letter grade is decided from the exact percentage, so 89.5% stays a B on the 10-point scale. Some teachers do round before assigning grades; if yours does, apply that rule yourself and say so when you report the grade.
Which grading scale should I choose?
Use the scale your school or exam board publishes. The built-in letter scale is the US 10-point scale from Florida law, which many US schools follow. For other countries or for a school with different cut-offs, choose "No letter grade" and read the percentage.
Can the percentage be more than 100%?
Yes, if you received bonus or extra-credit marks above the maximum. The calculator shows the result and a warning so you can double-check that the maximum marks are entered correctly.
Sources
Data last checked: 2026-10-13.
This tool runs entirely in your browser. What you enter or upload stays on your device and is never sent to our servers.