# How to Find Class Size (With Examples)

In statistics, class size refers to the difference between the upper and lower boundaries of a class in a frequency distribution.

The following examples shows how to find the class size for various frequency distributions.

### Example 1: Finding Class Size for Basketball Data

Suppose we have the following frequency distribution that describes the number of points scored by various basketball players in a league: The first class has a lower limit of 1 and an upper limit of 5. Thus, the class size would be calculated as:

• Class size: 5 – 1 = 4

The second class has a lower limit of 6 and an upper limit of 10. Thus, the class size would be calculated as:

• Class size: 10 – 6 = 4

No matter which class we analyze in the frequency distribution, we’ll find that the class size is 4

### Example 2: Finding Class Size for Sales Data

Suppose we have the following frequency distribution that describes the number of widgets sold by a certain company on different days: The first class has a lower limit of 1 and an upper limit of 10. Thus, the class size would be calculated as:

• Class size: 10 – 1 = 9

The second class has a lower limit of 11 and an upper limit of 20. Thus, the class size would be calculated as:

• Class size: 20 – 11 = 9

No matter which class we analyze in the frequency distribution, we’ll find that the class size is 9