Converting marks to a percentage is simple arithmetic, but mixing up totals or combining subjects incorrectly is a common source of error. Here's exactly how it works.
The Basic Formula
Percentage = (Marks Obtained ÷ Total Marks) × 100
A student scoring 68 out of 80 has: (68 ÷ 80) × 100 = 85%. The mistake many students make is comparing raw marks from exams with different totals directly — 68/80 and 85/100 represent the same percentage, but the raw numbers look very different.
Combining Multiple Subjects
To find an overall percentage across several subjects, add all marks obtained and divide by the sum of all possible totals — not by averaging each subject's individual percentage, which gives a subtly different (and usually incorrect) result unless every subject shares the same total marks.
Conclusion
Once you have an accurate percentage, converting it to a letter grade or GPA points is the natural next step — our Percentage to Grade Calculator does both instantly, with a grade scale you can customize.