Computers running Windows Vista or Windows 7 or Windows 8

Click the Start button or Windows button, right-click Computer, and then click Properties.

• If "64-bit Operating System" is listed next to System type, you’re running the 64-bit version of Windows Vista or Windows 7 or Windows 8.
• If "32-bit Operating System" is listed next to System type, you’re running the 32-bit version of Windows Vista or Windows 7 or Windows 8.

The edition of Windows Vista or Windows 7 or Windows 8 you're running is displayed under Windows edition near the top of the window.