Percentile Calculator

Calculate percentiles for your dataset or find the percentile rank of a specific value. This calculator helps you understand where values fall relative to your data distribution.

What are Percentiles?

A percentile indicates the value below which a given percentage of observations in a group of observations falls. For example, the 75th percentile (also called the third quartile) is the value below which 75% of the data points fall.

Common Percentiles

PercentileAlso Known As
25th percentileFirst Quartile (Q1)
50th percentileMedian, Second Quartile (Q2)
75th percentileThird Quartile (Q3)
10th percentileFirst Decile
90th percentileNinth Decile

Percentile Rank

The percentile rank of a value is the percentage of values in the dataset that are less than or equal to that value. For example, if a test score has a percentile rank of 80, it means the score is higher than 80% of all scores.

Applications

  • Standardized Testing: Understanding where a score falls relative to others
  • Growth Charts: Comparing children's measurements to reference populations
  • Performance Metrics: Identifying top or bottom performers
  • Data Analysis: Understanding data distribution and identifying outliers

Calculation Method

This calculator uses linear interpolation to calculate percentiles, which provides smooth estimates even when the exact percentile falls between two data points. This is the same method used by most statistical software.