A Percentile Rank Calculator

A percentile rank tells you what fraction of a group sits below a value. For 12th out of 250 there are 238 below, and the two standard conventions give 0.9558232931726908 and 0.952 — answers that differ by less than one person, yet must be kept distinct from the percentage score.

Position (1 is the highest)How many places from the top the value sits. 12th means 11 values are above it.Size of the groupThe number of values in the whole group, not just the ones below.

Percentile rank (n - 1 convention)

95.58%

Values below the position: 238
Values at or above the position: 12
Top share at or above: 4.80%

Values update as you type. This calculator covers the single scenario its formula assumes — see Common Mistakes for what it leaves out.

The formula this calculator uses

Percentile rank = count below / (n - 1), or count below / n

count below: Number of values below the one of interest — 238 here
n: Size of the group — 250 here
PR: Percentile rank as a proportion, such as 0.9558232931726908
top share: Fraction at or above, 12 / 250 = 0.048

How to check the result by hand

1
Decide what counts as below
Before counting, fix the rule: values strictly less than the one of interest, or values less than or equal to it. For a candidate at position 12 out of 250 with distinct scores, 250 - 12 = 238 values are strictly below.
2
Count the group below and record n
The count below is 238 and the group size is n = 250. Both numbers are needed, because every convention divides the first by a function of the second.
3
Choose the denominator convention
Use n - 1 = 249 to treat the group as a sample, or n = 250 to treat it as the full population. The sample convention gives 238 / 249 = 0.9558232931726908; the population convention gives 238 / 250 = 0.952.
4
Divide to obtain the rank
Perform the division to full precision and keep every digit, since 238 / 249 = 0.9558232931726908. Rounding early would hide the very small gap between the two conventions, which is only 0.0038232931726908.
5
Convert to a percentage and report
Multiply by 100 to express the rank as 95.58233%, or report the top share 12 / 250 = 0.048 = 4.8% instead. Always name the convention and the group size when you quote the result.

For worked examples, common mistakes and the limits of this formula, read the full How To Calculate A Percentile Rank page.