How it works
A percentile tells you the share of values that fall below a given point. If your score is at the 80th percentile, you scored higher than about 80% of the group.
To find the value at a percentile, the list is sorted and the position p ÷ 100 × (n − 1) is located, interpolating between neighbors when it lands between two values. This matches Excel’s PERCENTILE.INC and the default in many statistics packages.
To find the percentile rank of a value, the calculator counts values below it and adds half of any ties, then divides by the total. Different textbooks use slightly different conventions, so small differences from other tools are normal with short lists.
Formula
Value at p: position = p ÷ 100 × (n − 1), interpolated · Rank of x = (below + ½ equal) ÷ n × 100
Questions people ask
Is the 50th percentile the same as the median?
Yes. With the interpolation method used here, the 50th percentile equals the median.
What is the difference between a percentile and a percentage?
A percentage is a score out of 100, such as 85% correct. A percentile is a position relative to others: 85% correct might be the 60th percentile if many people scored higher.
Why does another calculator give a slightly different answer?
There are several accepted percentile definitions (Excel alone has INC and EXC). They agree closely for large data sets but can differ for short lists.