An Overview of COS Function | Microsoft Excel

The COS function is one of the math and trigonometry functions in Microsoft Excel. It can be used as a standalone function as well as in collaboration with the other functions. This article will give you an overview of the COS function in Excel.


The COS function calculates the cosine of an angle. The unit of the angle must be in radians.

If you have angles in degrees, multiply the angle with PI()/180 to convert it into degrees. Alternatively, you can use the RADIAN function to turn angles in degrees to angles in radians.




  • number: It refers to the angle in radian.


A numerical value in the range of -1 to 1.

Examples of COS Function

Suppose, you have an angle in radian 0.523598776 in cell A2. You can calculate the cosine of this angle using the COS function quite easily. To do that, you can use the formula:


The output will be 0.866025404 which is the cosine value of the angle 0.523598776 radians.

Here are some examples of the usage of the COS function.

Examples of COS Function in Excel

Usage Guide of COS Function

Step_1: Start with inserting an equal sign (=) in a blank cell.

Step_2: Then type COS.

Step_3: Type open parenthesis “(“.

As you type the open parenthesis, Excel shows the syntax of the COS function.

Usage Guide of COS Function in Excel

Step_4: Insert a number that is an angle in radians.

You can directly insert a number or a cell address that contains a number.

Here, I have inserted cell B2 which contains the angle in radians, 0.523598776.

Step_5: After that insert a closing parenthesis “)”.

Step_6: Finally press the ENTER button.

Usage Guide of COS Function in Excel

Final Result

The COS function returns 0.866025404. Here, the cosine of the angle 0.523598776 radians is 0.866025404. Thus, the output is 0.866025404.

Usage Guide of COS Function in Excel

Generate a Cosine Wave

To generate a cosine wave from the angles in radians and their corresponding cosine values,

Step_1: Select the data first.

Step_2: Go to the Insert tab.

Generate a Cosine Wave

Step_3: In the Charts group, click on Insert Scatter (X, Y) or Bubble Chart.

Step_4: From the Scatter section, select Scatter with Smooth Lines and Markers.

Generate a Cosine Wave

After that, you will get a beautiful cosine wave for a complete cycle.

Generate a Cosine Wave


  • Excel for Microsoft 365
  • Excel 2016
  • Excel for Microsoft 365 for Mac
  • Excel 2016 for Mac
  • Excel for the web
  • Excel 2013
  • Excel 2021
  • Excel 2010
  • Excel 2021 for Mac
  • Excel 2007
  • Excel 2019
  • Excel for Mac 2011
  • Excel 2019 for Mac
  • Excel Starter 2010


  • The COS function shows #VALUE! error in the case of the non-numeric values.
  • The maximum value that the COS function can return is
  • And the minimum value that the COS function can return is -1.


The COS function is one of the math and trigonometry functions in Excel. If you have any questions regarding the COS function, please comment below. Thanks!

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *