Percentile Rank of a Score Calculator

How it is calculated

The tool counts the data values that are strictly below your score (B) and the values equal to it (E), out of N values in total. The percentile rank is PR = (B + 0.5 × E) / N × 100. Tied values therefore count as half below and half above. Values are separated by spaces, commas or both, and every item must be a number, or the tool returns nothing. Because a comma is a separator, decimals must use a dot: typing 2,5 gives two values, 2 and 5. The score does not need to be in the list. A score below every value gives 0.0% and above every value gives 100.0%. The result is rounded to one decimal. This is the mid-rank definition; some textbooks count ties fully as below or not at all, which gives different numbers on tied data.

Common mistakes

• Using a comma as a decimal mark in the list. A comma separates values, so 2,5 becomes two numbers (2 and 5) and the count N is wrong; write 2.5.
• Reading the percentile rank as a percentage of correct answers. It is the position within the group, not the score itself: 55.0% means the score sits about halfway up the group.
• Entering only part of the data set, such as the top ten of fifty. N is the number of values you typed, so a partial list distorts the rank.
• Expecting a score tied with others to count as fully below them. Ties count half, which is why a score tied with others can sit at 20.0% rather than a round 10.0% or 30.0%.
• Adding your own score to the list when it is not part of the group. The score is then counted as one more tied value, N grows by 1 and the rank moves; leave it out unless it belongs to the group.