Question 1

What is a percentile rank?

Accepted Answer

A percentile rank tells you what percentage of scores in a dataset fall below a given value. For example, a score at the 90th percentile means it is higher than 90% of all other scores.

Question 2

What is the difference between percentile rank and percentile value?

Accepted Answer

Percentile rank takes a score and returns a percentage (how many values are below it). Percentile value does the reverse — you give a percentage (e.g. P90) and the tool returns the score at that position in the sorted dataset.

Question 3

Which interpolation methods are supported?

Accepted Answer

The tool supports six methods: exclusive, inclusive (default, used by Excel PERCENTILE.INC), lower, higher, nearest rank, and linear (NIST). Pick the one that matches your textbook or software.

Question 4

How do I enter my dataset?

Accepted Answer

Type or paste numbers separated by commas, spaces or newlines. The tool automatically parses them, sorts the dataset and shows the count, mean, median and standard deviation.

Question 5

Is my data private?

Accepted Answer

Yes. All calculations run entirely in your browser. No numbers are ever uploaded to a server.