P Percentile Calculator

Find precise percentile values from messy datasets quickly. Compare nearest-rank and interpolated methods with confidence. Visualize positions, export reports, and verify trends with ease.

Calculator Input

Example Data Table

Dataset	Percentile	Nearest Rank	Interpolated
12, 15, 18, 22, 24, 27, 31, 34, 39, 45	P25	18	19
12, 15, 18, 22, 24, 27, 31, 34, 39, 45	P50	24	25.5
12, 15, 18, 22, 24, 27, 31, 34, 39, 45	P75	34	33.25

Formula Used

Sort the dataset in ascending order first. Then use one of the following percentile methods.

Nearest Rank Method
r = ceil((p / 100) × n)
Pp = x(r)

Where:
p  = requested percentile
n  = total number of values
x(r) = value at rank r in the sorted list

Linear Interpolation Method
i = 1 + (p / 100) × (n - 1)
Pp = x(lower) + fraction × (x(upper) - x(lower))

Where:
i = fractional percentile position
lower = floor(i)
upper = ceil(i)
fraction = i - lower

How to Use This Calculator

Enter all dataset values in the textarea.
Separate numbers with commas, spaces, or line breaks.
Type the required percentile value between 0 and 100.
Select either linear interpolation or nearest rank.
Choose the number of decimal places.
Click the calculate button to see the result.
Review the result panel, chart, and sorted table.
Use the export buttons for CSV or PDF files.

Frequently Asked Questions

1. What does a percentile show?

A percentile shows the value below which a chosen percentage of observations falls in a sorted dataset.

2. What does the p in P percentile mean?

The p value is the target percentile level. For example, P90 means the 90th percentile.

3. Why are two methods available?

Different textbooks and software use different percentile rules. This calculator lets you compare the nearest-rank result with the interpolated result.

4. Can I enter unsorted values?

Yes. The calculator automatically sorts your values before applying the percentile formula.

5. Are repeated values allowed?

Yes. Duplicate numbers are valid and are included normally in percentile calculations.

6. What happens at P0 and P100?

P0 returns the minimum value, while P100 returns the maximum value in the dataset.

7. Why can the percentile value be non-integer?

Interpolated methods can create values between two data points. That often gives a smoother percentile estimate.

8. Is this calculator suitable for grouped data?

This version is designed for raw ungrouped numbers. Grouped frequency tables need class-boundary formulas instead.