Q1 is the 25th percentile, Q2 the median (50th), Q3 the 75th. IQR = Q3 − Q1 measures spread of the middle half.

Which method is used?

We use a common method: sort the data and use linear interpolation for quartile positions (e.g. inclusive or exclusive median).

Online Quartile Calculator

Compute Q1, Q2 (median), Q3, and IQR from comma-separated numbers. IQR = Q3 − Q1.

Numbers (comma-separated)

What are quartiles?: Q1 is the 25th percentile, Q2 the median (50th), Q3 the 75th. IQR = Q3 − Q1 measures spread of the middle half.
Which method is used?: We use a common method: sort the data and use linear interpolation for quartile positions (e.g. inclusive or exclusive median).

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