Pass arguments to a Windows batch script

David Y.

The Problem

How can I write a batch script that takes arguments from the command line?

The Solution

Batch scripts can access up to nine arguments from the command line using the syntax %1 to %9. For example, the script below will print out three provided arguments, each on their own line:

@echo off

echo %1
echo %2
echo %3
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If we save this script as echothree.bat, we can execute it as follows:

echothree.bat One Two Three
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This will produce the following output:

One
Two
Three
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%0 contains the name of the script and %* contains all specified arguments – this is useful if we want to allow a variable number of arguments, or if we want to pass all of the arguments to another script or program. For example, this script would produce the command used to execute it:

@echo off

echo %0 %*
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For longer scripts, we can create variables containing our argument values as follows:

@echo off

set name=%1
set type=%2

echo Processing %name% of %type% ...
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When dealing with numeric values rather than strings, we need to pass the /A flag to set:

@echo off

set /A a = %1
set /A b = %2
set /A sum = %a% + %b%

echo %sum%
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If we need to handle more than nine arguments, we can use the shift command. This command moves all argument values back by one – %1 is moved to %0, %2 is moved to %1, and the previously inaccessible tenth argument is moved to %9. We could also use this method to consume all arguments as %1, which may be useful when creating scripts that take arguments in any order (e.g. arguments with flags like -a and -b).

We could use shift to rewrite echothree.bat as follows:

@echo off

echo %1
shift
echo %1
shift
echo %1
shift
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Note that calling shift will not affect the value of %*.