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Formula verified · Deterministic calculation

Quartile Calculator

Enter a dataset and choose the first, second or third quartile to calculate its interpolated value.

Q11.75
CalcuMint Pro

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Result methodology

Deterministic calculation using the displayed formula and supplied inputs.

Solution steps
  1. Sorted count = 4
  2. Q1 position = 0.75
  3. Q1 = 1.75

How this calculator works

Quartile positions use h=(k/4)(n−1) with linear interpolation.

Formula

Qk at h=(k/4)(n−1), with linear interpolation

Computes Q1, Q2 or Q3 using the same linear-position convention as the percentile calculator.

Worked example

First quartile is a verified test case used by the calculation engine.

Assumptions and limitations

  • The dataset contains numeric observations.
  • The quartile is Q1, Q2 or Q3.
  • Linear interpolation follows the same position convention as the percentile calculator.

Methodology & sources

This calculator uses deterministic, versioned calculation logic. The formula and verified examples above are part of the calculation definition used by CalcuMint.

  • CalcuMint deterministic statistics engine

Frequently asked questions

What are Q1, Q2 and Q3?

They divide ordered data at the 25th, 50th and 75th percentile positions under the calculator's convention.

Is Q2 the median?

Yes. Q2 corresponds to the 50th percentile.

Related calculators

Percentile CalculatorCalculate a percentile using linear interpolation of ordered data.Interquartile Range CalculatorCalculate the interquartile range, Q1 and Q3 to understand the spread of the middle half of a numeric dataset.Mean Median Mode Range CalculatorCalculate mean, median, mode, minimum, maximum and range from a dataset.