Free Percentile Calculator

Estimate the value at a given percentile rank using linear interpolation between data bounds.

Estimated Value at Target Percentile

75.0000

Interpolation Fraction0.5000

Estimated Value at Target Percentile vs Value at Lower Rank

How to Estimate a Percentile by Interpolation

Formula

Value at P = Lower Value + Fraction * (Upper Value - Lower Value)

where Fraction = (Target Percentile - Lower Rank) / (Upper Rank - Lower Rank)

This linearly interpolates between two known ranked values. The kth percentile is the value below which k% of observations fall.

Example Calculation

The 40th percentile is 70 and the 60th percentile is 80. Estimate the 50th percentile.

  1. 01Fraction = (50 - 40) / (60 - 40) = 10 / 20 = 0.5
  2. 02Value at 50th percentile = 70 + 0.5 * (80 - 70)
  3. 03= 70 + 0.5 * 10 = 70 + 5 = 75

Frequently Asked Questions

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