Home Â» How to Calculate the Interquartile Range in Google Sheets

# How to Calculate the Interquartile Range in Google Sheets

The interquartileÂ range, often denoted IQR, is a way to measure the spread of the middle 50% of a dataset. It is calculated as the difference between the first quartile (Q1) and the third quartile (Q3) of a dataset.

Note that quartiles are simply values that split up a dataset into four equal parts.

The IQR is often used to measure the spread of values in a dataset because itâ€™s known to be resistant to outliers. Since it only tells us the spread of the middle 50% of the dataset, it isnâ€™t affect by unusually small or unusually large outliers.

This makes it a preferable way to measure dispersion compared to a metric like the range, which simply tells us the difference between the largest and the smallest values in a dataset.

This tutorial explains how to calculate the IQR for a given dataset in Google Sheets.

### Example: How to Calculate IQR in Google Sheets

Use the following steps to calculate the interquartile range (IQR) of a dataset in Google Sheets.

Step 1: Enter the data.

First, enter all of the values of a dataset into one column:

Step 2: Calculate the first and third quartiles.

Next, weâ€™ll use theÂ QUARTILE()Â function to calculate the first (Q1) and third (Q3) quartiles of the dataset.

Note that this function uses the following syntax:

QUARTILE(data, quartile_number)

where:

• data:Â An array of data values
• quartile_number: The quartile to calculate

The following image shows the formulas to use to calculate Q1 and Q3 for this dataset:

Step 3: Calculate the IQR.

Lastly, we can subtract the first quartile (Q1) from the third quartile (Q3) to obtain the interquartile range:

The interquartile range turns out to be 16. This tells us the spread of the middle 50% of values in our dataset.