Please Note: This article is written for users of the following Microsoft Excel versions: 2007, 2010, 2013, 2016, 2019, Excel in Microsoft 365, and 2021. If you are using an earlier version (Excel 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Excel, click here: Understanding Functions in Macros.

Understanding Functions in Macros

Written by Allen Wyatt (last updated March 12, 2022)
This tip applies to Excel 2007, 2010, 2013, 2016, 2019, Excel in Microsoft 365, and 2021


You already know that you can use subroutines in your macros. VBA also allows you to define functions that can be used in your macros. The difference between functions and subroutines is that functions can return values, whereas subroutines cannot. Consider the following macro:

Sub Macro1()
    TooMany = TestFunc
    If TooMany Then MsgBox "Too many columns selected"
End Sub
Function TestFunc() As Boolean
    TestFunc = False
    If Selection.Columns.Count > 10 Then
       TestFunc = True
    End If
End Function

The macro (Macro1) calls the TestFunc function. This function returns either the value False or True, depending on a test it performs. Macro1 then acts upon the value returned. Notice that the function name can appear on the right side of an equal sign. This makes functions very powerful and an important part of any program. Within the function the result is assigned to TestFunc, which is the name of the function itself; this is the value returned by the function.

As with subroutines, you can also pass parameters to your functions. This is illustrated in the following macro:

Sub Macro1()
    A = 12.3456
    MsgBox A & vbCrLf & RoundIt(A)
End Sub
Function RoundIt(X) As Integer
    RoundIt = Int(X + 0.5)
End Function

This simple macro (Macro1) defines a number, and then uses a message box to display it and the result of passing the number to the RoundIt function. The output is 12.3456 and 12. Notice that the parameter should be passed to the function within parentheses. Also notice that the function does not use the same variable name as it was passed. This is because VBA reassigns the value of X (what the function needs) so it matches the value of A (what the program is passing to the function). The important thing to remember in passing parameters to functions is that your program must pass the same number of parameters as the function expects and the parameters must be of matching types and in the proper order.

Note:

If you would like to know how to use the macros described on this page (or on any other page on the ExcelTips sites), I've prepared a special page that includes helpful information. Click here to open that special page in a new browser tab.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (11765) applies to Microsoft Excel 2007, 2010, 2013, 2016, 2019, Excel in Microsoft 365, and 2021. You can find a version of this tip for the older menu interface of Excel here: Understanding Functions in Macros.

Author Bio

Allen Wyatt

With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He is president of Sharon Parq Associates, a computer and publishing services company. ...

MORE FROM ALLEN

Removing Space Before Paragraphs

Want to quickly format a paragraph to remove any extra space before it? Word includes a tool that can make this change a ...

Discover More

Sharing AutoText Entries in a Network

Creating AutoText entries can be a great way to improve your productivity with Word. At some point you may want to share ...

Discover More

Preventing Printing

When dealing with determined users, it is virtually impossible to prevent information in your document from being ...

Discover More

Excel Smarts for Beginners! Featuring the friendly and trusted For Dummies style, this popular guide shows beginners how to get up and running with Excel while also helping more experienced users get comfortable with the newest features. Check out Excel 2013 For Dummies today!

More ExcelTips (ribbon)

Automatically Enabling Macros for Specific Workbooks

On your system you may have workbooks that contain macros you know are safe to use. Microsoft provides two things you can ...

Discover More

Macro for Month Name

Need to know how to generate a full month name based on a date? It's easy to do, as discussed in this tip.

Discover More

Macro Runs Slowly, but Steps Quickly

When you have a macro that processes a huge amount of data, it can seem like it takes forever to finish up. These ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments

If you would like to add an image to your comment (not an avatar, but an image to help in making the point of your comment), include the characters [{fig}] (all 7 characters, in the sequence shown) in your comment text. You’ll be prompted to upload your image when you submit the comment. Maximum image size is 6Mpixels. Images larger than 600px wide or 1000px tall will be reduced. Up to three images may be included in a comment. All images are subject to review. Commenting privileges may be curtailed if inappropriate images are posted.

What is 7 + 0?

There are currently no comments for this tip. (Be the first to leave your comment—just use the simple form above!)


This Site

Got a version of Excel that uses the ribbon interface (Excel 2007 or later)? This site is for you! If you use an earlier version of Excel, visit our ExcelTips site focusing on the menu interface.

Newest Tips
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.