The semi-interquartile range is a way to measure the spread of observations in a dataset. It is calculated as one half the distance between the first quartile (Q1) and the third quartile (Q3):

Semi-interquartile range = (Q3 – Q1) / 2

This calculator finds the semi-interquartile range for a given dataset.

Simply enter the list of the comma-separated values for the dataset, then click the “Calculate” button:

45, 47, 52, 52, 53, 55, 56, 58, 62, 80

Q1: 52.0000

Q3: 57.5000

Semi-interquartile range: 2.7500