Batch Script Arithmetic Operators

Arithmetic Operators

The batch script language supports arithmetic operators to perform sums, differences, multiplications, divisions and modulus.

The following table lists the available arithmetic operators.

Operator	Description	Example
+	Addition of two operands	1 + 2 will give 3
−	Subtracts second operand from the first	2 − 1 will give 1
*	Multiplication of both operands	2 * 2 will give 4
/	Division of the numerator by the denominator	3 / 2 will give 1.5
%	Modulus operator and remainder of after an integer/float division	3 % 2 will give 1

Example

The following code snippet shows how the various operators can be used.

Example of Arithmetic Operators

@echo off
set /A a=5
set /A b=10
set /A c= %a%+%b%
echo %c%
set /A c= %a%-%b%
echo %c%
set /A c= %b%*%a%
echo %c%
set  /A c=%b%/%a%
echo %c%
set /A c=%b% %% %a%
echo %c%

15
-5
50
2
0

Precedence of Arithmetic operators

The precedence of arithmetic operators is in the following order:

/  *  %  +  -

note

The expression enclosed inside ( ) gets the highest priority in the precedence.

Let's clarify this with the following example:

PrecedenceExample.bat

@echo off
set /A s = (20 - 5) * 2 + 8 / 2
echo s = %s%

s = 34

Explanation:

• (20 - 5) gets the highest priority and calculated first giving 15.
• Then division operator / gets next priority thus 8 / 2 is evaluated giving 4.
• After this multiplication operator * gets next priority thus 15 * 2 yields 30.
• Finally, addition operator + performs addition operation 30 + 4 giving final result 34.