Enter the total number of observations and the total number of classes into the calculator to determine the class frequency.

Class Frequency Formula

The following formula is used to calculate a class frequency. 

CF = TO / TC
  • Where CF is the class frequency
  • TO is the total number of observations/data points in the data set
  • TC is the total number of classes in the data set

To calculate the class frequency, divide the total number of observations by the total number of classes in the data set.

What is class frequency?

Class frequency is the average number of observations per class in a given data set or sample.

In other words, if there are 100 observations and 10 different classes, then the class frequency would be 100/10 = 10 observations per class.

How to calculate class frequency?

The following example problem outlines the steps to calculate a class frequency of a sample of data.

First, determine the total number of observations. For this example problem, there are a total of 5,000 observations.

Next, determine the total number of classes these observations are broken into. In this case, the total number of classes is determined to be 8.

Finally, calculate the class frequency using the formula and information from the previous steps.

CF = TO / TC

CF = 5000 / 8

CF = 625 observations / class