A percentile rank is the percentage of scores in a group that fall at or below a given score, used to show how one result compares with everyone else’s.
If your percentile rank is 75, you scored as well as or better than about 75% of the comparison group.
The formula
A common version:
Percentile rank = (B + 0.5 × E) ÷ N × 100
- B = number of scores below yours
- E = number of scores equal to yours (including yours)
- N = total number of scores
Example. In a class of 30, a student’s 82 beats 24 classmates and ties with one other (so E = 2):
(24 + 0.5 × 2) ÷ 30 × 100 = 25 ÷ 30 × 100 = 83rd percentile
Some sources count only scores strictly below yours, which gives a slightly lower number (80 here). Both conventions are in use.
Percentile vs. percent correct
This is the most common mix-up. A score of 70% on a brutal test might be the 95th percentile. A percentile depends entirely on who else took the test, which is also how a bell-curve grading on a curve assigns letters.
Where you’ll see it
The College Board’s SAT score guide says score reports include percentiles that compare your scores with other students who took the same test. The SAT score calculator and PSAT score calculator give you the scaled scores those percentiles are based on. Teachers can see class distributions with the grade curve calculator, and selection programs like National Merit work on similar rank-based cutoffs.