VBA Variables, Data Types & Declare VBA Constants in Excel

Variables are used in almost all computer program and VBA is no different. It's a good practice to declare a variable at the beginning of the procedure. It is not necessary, but it helps to identify the nature of the content (text, data, numbers, etc.)

In this VBA tutorial, you will learn-

VBA Variables

Variables are specific values that are stored in a computer memory or storage system. Later, you can use that value in code and execute. The computer will fetch that value from the system and show in the output. Each of the Excel VBA variable types must be given a name.

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To name the variable in VBA, you need to follow the following rules.

It must be less than 255 characters
No spacing is allowed
It must not begin with a number
Period is not permitted

Here are some example for Valid and Invalid names for variables in VBA.

Valid Names Invalid Names

My_Watch

My.Watch

NewCar1

1_NewCar (not begin with number)

EmployeeID

Employee ID ( Space not allowed)

In VBA, we need to declare the variables before using them by assigning names and data type.

In VBA, Variables are either declared Implicitly or Explicitly.

Implicitly: Below is an example of a variable declared Implicitly.
label=guru99
volume=4
Explicitly: Below is an example of variable declared Explicitly. You can use "Dim" keyword in syntax
Dim Num As Integer
Dim password As String

VBA variable is no different than other programming languages. To declare a variable in VBA you use the keyword "Dim."

Syntax for VBA Variable,

To declare a variable in VBA, type Dim followed by a name:

Sub Exercise ()Dim <name>End Sub

Before we execute the variables we have to record a macro in Excel. To record a macro do the following -

Step 1): Record the Macro 1

Step 2) : Stop Macro 1

Step 3): Open the Macro editor, enter the code for variable in the Macro1

Step 4): Execute the code for Macro 1

Example, for VBA Variable

Sub Macro1()Dim Num As IntegerNum = 99MsgBox " Guru " & NumEnd Sub

When you run this code, you will get the following output in your sheet.

Excel VBA Data Types

Computer cannot differentiate between the numbers (1,2,3..) and strings (a,b,c,..). To make this differentiation, we use Data Types.

VBA data types can be segregated into two types

Numeric Data Types

TypeStorageRange of ValuesByte1 byte0 to 255Integer2 bytes-32,768 to 32,767Long4 bytes-2,147,483,648 to 2,147,483,648Single4 bytes-3.402823E+38 to -1.401298E-45 for negative values 1.401298E-45 to 3.402823E+38 for positive values.Double8 bytes-1.79769313486232e+308 to -4.94065645841247E-324 for negative values 4.94065645841247E-324 to 1.79769313486232e+308 for positive values.Currency8 bytes-922,337,203,685,477.5808 to 922,337,203,685,477.5807Decimal12 bytes+/- 79,228,162,514,264,337,593,543,950,335 if no decimal is use +/- 7.9228162514264337593543950335 (28 decimal places)

Non-numeric Data Types

Data TypeBytes UsedRange of ValuesString (fixed Length)Length of string1 to 65,400 charactersString (Variable Length)Length + 10 bytes0 to 2 billion charactersBoolean2 bytesTrue or FalseDate8 bytesJanuary 1, 100 to December 31, 9999Object4 bytesAny embedded objectVariant(numeric)16 bytesAny value as large as DoubleVariant(text)Length+22 bytesSame as variable-length string

In VBA, if the data type is not specified, it will automatically declare the variable as a Variant.

Let see an example, on how to declare variables in VBA. In this example, we will declare three types of variables string, joining date and currency.

Step 1) Like, in the previous tutorial, we will insert the commandButton1 in our Excel sheet.

Step 2) In next step, right-click on the button and select View code. It will open the code window as shown below.

Step 3) In this step,

Save your file by clicking on save button
Then click on Excel icon in the same window to return the Excel sheet.
You can see the design mode is "on" highlighted in green

Step 4) Turn off design mode, before clicking on command button

Step 5) After turning off the design mode, you will click on commandButton1. It will show the following variable as an output for the range we declared in code.