Follow these instructions to determine whether your computer is running a 32-bit or a 64-bit edition of Microsoft Windows.

Identify 32-bit and 64-bit editions of Windows 7 and Vista

If your computer uses Windows 7 or Vista, then do the following:

  1. Choose Start > Control Panel.
  2. Do one of the following:
    • If the Control Panel is in a category view, then click System And Maintenance. On the next screen, click System.
    • If the Control Panel is in Classic View, then double-click System.
  3. Look for 32-bit Operating System or 64-bit Operating System next to System Type.

Identify 32-bit and 64-bit editions of Windows XP

If your computer uses Windows XP, then do the following:

  1. Choose Start > Control Panel (or Start > Settings > Control Panel).
  2. Do one of the following:
    • If the Control Panel is in a Category View, then click Performance And Maintenance. On the next screen, click See Basic Information About Your Computer.
    • If the Control Panel is in Classic View, then double-click System.
  3. In the System Properties window, click the General tab.
  4. If the text beneath System says Microsoft Windows XP Professional x64 Edition, then you are running a 64-bit edition of Windows XP. Otherwise, you are running a 32-bit edition.

Additional information

The System item in the Control Panel shows basic information about your computer, including the specific edition of Windows that is installed.