Interquartile Range (IQR)

The interquartile range (IQR) measures the spread of the middle 50% of a dataset: IQR = Q3 − Q1. Unlike the range, it isn't affected by extreme outliers.

If Q1 = 10 and Q3 = 22, then IQR = 22 − 10 = 12.

Compute the IQR from Q1 and Q3, or find it directly from a sorted dataset.

Continue exploring related topics:

• Quartiles - Splitting Data into Four Parts
• Range - Measuring the Spread of Data
• Outliers - Identifying Unusual Values