Find any percentile of a data set, or the percentile rank of a value, with quartiles and interquartile range.
Understanding the percentile calculation
There is more than one accepted way to compute a percentile, and different methods can give different answers on small data sets. The calculator shows both the linear interpolation method used by most statistical software and the simpler nearest-rank method.
Quartiles and the interquartile range come from the same calculation and are shown alongside, since they are what box plots and outlier tests are built on.
Getting your answer
- Paste your data, separated by commas, spaces or new lines.
- Enter the percentile you want.
- Enter a value to find its percentile rank instead.
The maths behind it
The default scenario, worked through
Worked through, a data set of 12, 15, 18, 22, 25, 27, 31, 34, 38, 44 produces a percentile value of 33.25. Underneath, Nearest-rank method comes out at 34 (rank 8 of 10) and Percentile rank of your value at 55%. Change any field and every figure updates as you type.