Weighted Values Percentile Calculator

Find a weighted percentile using the cumulative weight of ordered observations. Zero-weight values are excluded, including at percentile 0.

How to use Weighted Values Percentile Calculator

1. Enter Values and Weights as matching lists where weights are used; separate numbers with commas, spaces, semicolons or new lines. 2. Enter Percentile from 0 to 100. 3. Select Calculate or press Enter, then read weighted percentile. 4. Copy result copies the answer; Reset clears the form. Do not use thousands separators inside lists.

Why use this tool?

Find an observed value at a chosen cumulative weight threshold in a frequency or weighted dataset.

How the calculation works

Exclude zero-weight entries and sort the remaining value-weight pairs. Return the first value whose cumulative weight reaches percentile ÷ 100 × total weight. Percentile 0 returns the smallest positive-weight value and 100 returns the largest. This inverse empirical-CDF convention does not interpolate. It can differ from unweighted R-7 percentiles even when weights are equal. Results use up to six decimal places, or six significant digits in scientific notation for nonzero magnitudes below 0.000001. Calculations use browser floating-point arithmetic. Each list supports up to 20,000 numbers. Entry and result magnitudes must not exceed 9,007,199,254,740,991; unrepresentable variance or weighted products are rejected. General descriptive-statistics reference: https://itl.nist.gov/div898/handbook/prc/section2/prc262.htm. Weighted conventions are defined explicitly on this page.

Example

Values = 10,20,30, Weights = 1,1,2 and Percentile = 75 set a target cumulative weight of 3. Value 30 first reaches that threshold. With values 1,2,3 and weights 0,1,1, percentile 0 returns 2.

Practical tip

Use the same quantile convention when comparing another package, and keep every value paired with its own weight.