Check your Windows 8, Windows 7 or Windows Vista whether it’s a 32-bit or 64-bit version
Computers running Windows Vista or Windows 7
- Click the Windows Start button, right-click Computer, and then click Properties (or press Win + Pause/Break).
- If "64-bit Operating System" is listed next to System type, you’re running the 64-bit version of Windows.
- If "32-bit Operating System" is listed next to System type, you’re running the 32-bit version of Windows.
The edition of Windows 8, Windows 7 or Windows Vista you're running is displayed under Windows edition near the top of the window.[
source]
