The article about the way to build an automatic calendar is one of the most viewed on this website. But it is also the one with the most comments about the VBA code.
The purpose of this article is to explain each line of code and the logic of the program.
Sub Hide_Day() Dim Num_Col As Long 'This instruction cleans the content of the cells in your calendar Range("B7:AF13").ClearContents For Num_Col = 30 To 32 ' Test if the month of the cells (row 6) is the same of the month selected (cell A1 or cells(1,1)) If Month(Cells(6, Num_Col)) >= Cells(1, 1) Then Columns(Num_Col).Hidden = True Else Columns(Num_Col).Hidden = False End If Next End Sub
Line 1: Creation of the name of the subroutine
In any VBA program all the code is written inside subroutines (Sub
). Each subroutine must have a unique name in the project.
This name will be used in the calendar project to link the code with the dropdown list.
Sub Hide_Day()
Line 2 : Declare the variable
To evaluate the day's value in the different columns, we need a create variable in order to read each column index (1, 2, 3, ....)
The variable Num_Col
is declared (Dim
) as a Whole Number (As Long
) because the column index is obviously without decimal
Dim Num_Col As Long
Line 3 : Beginning of the loop
Now, we are going to create a loop to extend the variable Num_Col
from 30 till 32.
For Num_Col = 30 To 32
The reason why we start at the value 30 it's because for any month, the days 29, 30 et 31 will be always in columns 30, 31 and 32

Line4 : Test between the month calculated in the cells and the month selected
Here is the trick of the program 😉😎
How Excel calculates date?
As you know, all the months have 28 days. But February could have 29 days each 4 years and 4 months have 30 days (April, June, September, November).
Just like that, it seems complex to create a test for each case. But on the other hand, Excel calculates precisely a date even if the number of days to add extend to the end of the month.
For instance, if we add 30 days to the 1st February 2019, Excel will return the date of the 3rd March 2019.
=DATE(2019;2;1)+30 => 03/03/2019

How to code a cell in VBA
In VBA, to read the contents of a cell, you just have to write Cells(index row, index column)
. So for A1, you will write Cells(1, 1)
and for the cell AD6 with day 29, the code is Cells(6, 30)
But you can also replace one of the arguments of Cells
by a variable like this Cells(6, Num_Col)
Construction of the test
Back to the calendar, for the month of February 2019, columns 30, 31 and 32 will have dates of March (and not February) because of the rule explained in the previous formula.
So, we will write a test between the month (return by the VBA function Month
) of columns 30, 31 et 32 and the value returned by the dropdown menu for the month.

So, the test will check if the month in the cells AD6, AE6 and AF6 (or Cells(6, 30), Cells(6, 31) et Cells(6,32)
) is greater or equal to A1 (the cell linked to the dropdown menu for the month). But we don't need to test the 3 columns, the variable will do it for us 😀
If Month(Cells(6, Num_Col)) >= Cells(1, 1) Then
Line 5 : Hide the column
If the test is True, the column Num_Col
is hidden (Hidden = True
).
Columns(Num_Col).Hidden = True
Line 6 and 7 : Unhide the column
Otherwise (Else
), which means the test is False, then the column Num_Col
is un-hidden (Hidden = False
)
Else Columns(Num_Col).Hidden = False
This test looks stupid but in the case, your selected month has 31 days, you want to be able to display the previous column hidden (sooo clever 😉)
Line 8 and 9 : Close the instructions
In VBA, when you create a test or a loop, you must indicate when the test or the loop is ended.
At the end of the test If
is End If
, and the loop For
, you must write the instruction Next
End If Next
Line 10 : Clear the data
After the loop on the 3 columns, the program will clear the contents of the range B6 to AF13 Range("B6:AF13")
with the instruction ClearContents
Range("B6:AF13").ClearContents
Line 11 : End of the subroutine
Exactly like to indicate the end of a test or a loop, you must indicate that your subroutine is ended with the instruction End Sub
End Sub
22/02/2023 @ 16:41
How can I make the data stay for each month?
18/03/2023 @ 08:33
I will publish a workbook with this functionality soon
22/02/2023 @ 16:39
Great explanation! How can I make the data stay put each month?
Thanks!
24/01/2023 @ 14:02
How to leave the contents in the table. Contents do not remain when I change the months. May I know what should be the command for different content per month
08/01/2023 @ 16:18
Sir, very nice teaching methods ods, pls introduce vba code
06/12/2022 @ 22:36
I just stumbled upon this and it is amazing what i have learned. Thank you.
But in reviewing other comments, is there any way that final piece (storing the data entered on the calendar from month to month?
16/12/2022 @ 10:25
Soon 😉
06/10/2022 @ 11:48
formula is wrong, it should be If Month(Cells(6, Num_Kol)) > Cells(1, 1) Then
instead of If Month(Cells(6, Num_Kol)) > =Cells(1, 1) Then
04/02/2022 @ 19:04
It is a HTML conversion error...change the line to this:
If Month(Cells(6, Num_Col)) > Cells(1, 1) Then
26/01/2022 @ 12:32
I actually have the same problem. If I select "February" the visualized days are 28, but then, if I chose another month, let's say "January", the visualized days are still 28 and not 31.
Is there a way to solve this issue?
Thank you
23/12/2021 @ 16:11
Hello, I need to track vacation days in this calendar can you tell me how to adjust the code so that It keeps the days marked as vacation or off and not wipe them out? thank you
05/10/2021 @ 22:36
Hi Sir!
The code not working.. How I can solve?
Sub Hide_Day()
Dim Num_Col As Long
'This instruction cleans the content of the cells in your calendar
Range("B7:AF13").ClearContents
For Num_Col = 30 To 32
' Test if the month of the cells (row 6) is the same of the month selected (cell A1 or cells(1,1))
If Month(Cells(6, Num_Col)) >= Cells(1, 1) Then
Columns(Num_Col).Hidden = True
Else
Columns(Num_Col).Hidden = False
End If
Next
End Sub
16/11/2021 @ 19:35
Sub Hide_Day()
Dim Num_Col As Long
'This instruction cleans the content of the cells in your calendar
Range("B7:AF13").ClearContents
For Num_Col = 30 To 32
' Test if the month of the cells (row 6) is the same of the month selected (cell A1 or cells(1,1))
If Month(Cells(6, Num_Col)) Cells(1, 1) Then
Columns(Num_Col).Hidden = True
Else
Columns(Num_Col).Hidden = False
End If
Next
End Sub
16/11/2021 @ 19:40
The site is missing the not equal sign in the code between.
If Month(Cells(6, Num_Col)) equal sign Cells(1, 1) Then
17/11/2021 @ 18:42
Thanks, I check that
28/01/2021 @ 18:05
Great Sir can I make this in Google sheet please
28/01/2021 @ 18:15
VBA isn't available with Google Sheet. Only for Excel
16/11/2020 @ 21:28
Hi Sir!
I have a question regarding VBA Formula for column hide. Can you kindly assist me?
16/11/2020 @ 21:47
I have added a link for the explanation of the code. This will help you to customize your project
01/12/2021 @ 11:16
For me it seems it hides columns 30-32 regardless of the day when I use this formula. (calendar made same as your guide)
It seems like it checks for February and stays there, any way to circumvent that?