How to Determine if Windows is x64 or x86

When purchasing software or downloading patches and upgrades to Microsoft Windows, it is necessary to determine which bit count edition of the operating system your computer is running. The built-in System Information program gives information on your computer hardware and operating system. One of two editions of Windows will show in the "System Type" box. X86 denotes the 32-bit edition of Windows and x64 is the 64-bit edition. Downloads from the Microsoft website should match the system type as noted in System Information or the install will not complete correctly.

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Determine whether Windows is x64 or x86.

Windows Vista and Windows 7

Step

Click the "Start" button, type "System" in the search box and press "Enter."

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Click the "System Summary" option in the left navigation pane.

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Find "System Type" in the right informational window and make note of your system's edition.

Windows XP

Step

Click the "Start" button and choose "Run."

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Type in "sysdm.cpl" in the search box.

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Click the "General" tab. If Windows lists "X64 Edition," it is a 64-bit version of Windows, if it does not list an edition, it is a X86 32-bit edition.