Key takeaways
- Percentage = (Marks Obtained ÷ Total Marks) × 100.
- Marks obtained always goes on top, total marks always on the bottom.
- Don't forget the final ×100 step, or you'll be left with a decimal, not a percentage.
- To combine subjects, add all marks obtained and all totals first, then calculate one overall percentage.
In this guide
What is marks percentage?
Marks percentage converts the marks you scored on a test into a value out of 100, so it's easy to compare with other students, other exams, or a grading scale, no matter how many total marks each exam was worth.
Why does marks percentage matter?
A raw score like "68 out of 80" is hard to compare with "170 out of 200" at a glance. Converting both to percentages (85% and 85%) instantly shows they're actually identical performances.
Two exams with completely different totals can represent the exact same performance once converted to a percentage — that's the whole point of using one.
The formula
| Symbol | What it means | Example |
|---|---|---|
| Marks Obtained | The number of marks you actually scored | 68 |
| Total Marks | The maximum number of marks possible on the exam | 80 |
| Percentage | Your score out of 100 | 85% |
How to calculate marks percentage step by step
- 1Note down the marks you obtained and the total marks the exam was out of.
- 2Divide the marks obtained by the total marks:
68 ÷ 80 = 0.85. - 3Multiply that result by 100 to get your percentage:
0.85 × 100 = 85. - 4Compare your percentage against your school or exam board's grading scale to find your grade.
Enter your own marks obtained and total marks in the calculator below to see the working, including a letter grade.
Try it yourself
Pre-filled with the example — change any value.
Common mistakes to avoid
- Forgetting to multiply by 100. A decimal like 0.85 needs to become 85% to be read as a percentage.
- Averaging percentages from exams with different totals incorrectly. Combine total marks obtained and total marks possible first, then calculate one overall percentage, rather than just averaging separate percentages.
- Rounding too early, which can shift you across a grade boundary by mistake.
Tips and tricks
- For multiple subjects, this is just the general percentage formula applied to marks, so the same rules apply.
- Convert back the other way by multiplying the percentage (as a decimal) by the total marks, to check how many marks a target percentage needs.
- Your overall marks percentage often feeds into calculating a GPA on a grade-point scale.
Where you'll use it in real life
- Exams: checking your score right after a test or assignment.
- Report cards: calculating an overall percentage across a term or year.
- Scholarships: meeting a minimum percentage requirement for eligibility.
- College applications: converting marks into a standard percentage that admissions offices can compare.
Quick summary
To calculate a marks percentage, divide the marks obtained by the total marks, then multiply by 100. Keep your score on top and the total on the bottom, and compare the result against your grading scale. Try the calculator above with your own marks.
Worked example
You scored 68 marks out of a possible 80 on your math exam. What percentage did you score, and what grade does that give you?
- 01Percentage = (Marks Obtained ÷ Total Marks) × 100
- 02= (68 ÷ 80) × 100
- 03= 0.85 × 100
- 04= 85%
- 05Grade = A
These numbers are pre-filled in the calculator above.
Frequently asked questions
How do I calculate my percentage if I have marks from several subjects?
Add up the marks you obtained across all subjects, add up the total possible marks across all subjects, then divide the sum obtained by the sum total and multiply by 100.
What percentage is considered a passing grade?
This depends on the school or exam board, but many systems use 40% as a common minimum passing mark, while others set the bar higher, such as 50% or 60%.
How do I convert a percentage back into marks?
Multiply the percentage (as a decimal) by the total marks. For example, 85% of 80 total marks is 0.85 × 80 = 68 marks.
Can my marks percentage be higher than 100%?
Not usually. Since marks obtained can't normally exceed the total marks possible, the percentage is capped at 100% unless a test awards bonus marks above the stated total.
