Percentile Calculator

Percentile calculator

Find any percentile of a data set — the value below which a given percentage of observations fall — and the percentile rank of any value you choose. It is useful for test scores, benchmarks, salary bands, quartiles and any statistics work where position within a distribution matters more than the raw number.

How it works

The tool sorts your numbers, then for the Nth percentile uses linear interpolation between the closest ranks (the inclusive PERCENTILE.INC method):

rank = (p / 100) × (n − 1)
value = data[floor(rank)] + frac × (data[ceil(rank)] − data[floor(rank)])

For a value’s percentile rank, it counts the values at or below it, scoring ties as half:

rank% = (below + 0.5 × equal) / n × 100

The 50th percentile equals the median.

Example

Data set 12, 15, 17, 20, 22, 25, 30, 35, 40, 50 (n = 10):

• 90th percentile: rank = 0.9 × 9 = 8.1 → between 40 and 50 → 40 + 0.1×(50−40) = 41
• Percentile rank of 30: 6 values are below it (none tied) → 6 ÷ 10 × 100 = 65% (counting 30 itself by mid-rank convention raises this slightly)

Everything is sorted and calculated in your browser — nothing is uploaded.