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Interquartile Range Calculator

Compute the interquartile range (IQR = Q3 − Q1) and the fences used to flag outliers.

Also known as iqr calculator, interquartile range, outlier calculator.

Enter values

Separate values with commas, spaces or new lines.

Results update as you type.

Result

IQR

3

Q1
4
Q3
7
Lower fence
-0.5
Upper fence
11.5
Outliers
25

About the Interquartile Range Calculator

Compute the interquartile range (IQR = Q3 − Q1) and the fences used to flag outliers.

Also known as: iqr calculator, interquartile range, outlier calculator, inner fences.

How to use this calculator

  1. Enter data set.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Interquartile Range formula

IQR = Q3 − Q1 · fences = Q1 − 1.5·IQR, Q3 + 1.5·IQR

Worked example

Using the values pre-filled in the calculator above:

  • Data set: 1, 3, 4, 5, 5, 6, 7, 11, 25

the calculator returns:

  • IQR: 3
  • Q1: 4
  • Q3: 7
  • Lower fence: -0.5