Detect whether current Windows version is 32 bit or 64 bit

windows batch-file 64-bit
Clay Nichols picture Clay Nichols · Mar 2, 2009 · Viewed 124.7k times · Source

Believe it or not, my installer is so old that it doesn't have an option to detect the 64-bit version of Windows.

Is there a Windows DLL call or (even better) an environment variable that would give that information for Windows XP and Windows Vista?

One possible solution

I see that Wikipedia states that the 64-bit version of Windows XP and Windows Vista have a unique environment variable: %ProgramW6432%, so I'm guessing that'd be empty on 32-bit Windows.

This variable points to Program Files directory, which stores all the installed program of Windows and others. The default on English-language systems is C:\Program Files. In 64-bit editions of Windows (XP, 2003, Vista), there are also %ProgramFiles(x86)% which defaults to C:\Program Files (x86) and %ProgramW6432% which defaults to C:\Program Files. The %ProgramFiles% itself depends on whether the process requesting the environment variable is itself 32-bit or 64-bit (this is caused by Windows-on-Windows 64-bit redirection).

Answer

Dror Harari picture Dror Harari · Dec 2, 2009

To check for a 64-bit version of Windows in a command box, I use the following template:

test.bat:

@echo off
if defined ProgramFiles(x86) (
    @echo yes
    @echo Some 64-bit work
) else (
    @echo no
    @echo Some 32-bit work
)

ProgramFiles(x86) is an environment variable automatically defined by cmd.exe (both 32-bit and 64-bit versions) on Windows 64-bit machines only.

Related questions

How do I shutdown, restart, or log off Windows via a bat file?

I've been using Remote Desktop Connection to get into a workstation. But in this environment, I cannot use the power options in Start Menu. I need an alternative way to shutdown or restart. How do I control my computer's power …

Read More
How do I get current date/time on the Windows command line in a suitable format for usage in a file/folder name?

Update: Now that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date. See @npocmaka's https://stackoverflow.com/a/19799236/8479 What's a Windows command line statement(…

Read More
Batch file to delete files older than N days

I am looking for a way to delete all files older than 7 days in a batch file. I've searched around the web, and found some examples with hundreds of lines of code, and others that required installing extra command line …

Read More