How can I tell if I'm running 32-bit Windows or 64-bit Windows?

You are by no means the first person to hit this particular stumbling block, and when I show you how to ascertain which version you're running in Microsoft Windows Vista, you'll likely be rather surprised how hard Microsoft's made it to figure this important issue out!

As Microsoft describes: "The terms 32-bit and 64-bit refer to the way a computer's processor (also called a CPU), handles information. The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system."

Not so useful, really, but the short answer to the question "should I bother to even run 64-bit Windows?" is yes. If your hardware can run the 64-bit version of Windows, then you should definitely do so. Generally, it'll select for you when you're installing it. In fact, when I tried to install a 32-bit version of Windows 7 on my new Dell laptop, it complained and forced me to install the 64-bit version!

Now, how to tell?

I'll show you with Vista, then I'll show you how to tell if you're running 32-bit Windows 7 or 64-bit Windows 7 too, just for good luck.

In Vista, go to the START button (I know, I know, it's just the glowing Windows logo on the lower left corner of the widow, but old habits die hard with us tech writers) and choose "Control Panel". You'll see this:

Click on "System and Maintenance" and you'll see a bunch of choices, but right at the top, in the cheerily named "Welcome Center" section, you'll see:

Ah, you think you're done, don't you? Click on "Find which version of Windows you're using" and ...

So it shows you that you're running Windows Vista, but still doesn't indicate 32-bit or 64-bit versions, so we still haven't found what we need!

Click on "Show more details" on the top right and now you get a more useful display of system information about your computer, as I do about mine:

It's a bit hard to see the details, so I've zoomed in:

As you can see, I am indeed running a 64-bit version of Microsoft Windows Vista.

If you're running Windows 7 (aka win7) then it's a slight bit different because when you go to Control Panel you instead see:

At this point since there's no convenient shortcut, click on the word "System" instead. Now you'll get the same sort of detailed information display, half-way down showing:

And so you can see that I have a 64-bit version of Windows Vista running on one of my computers and a 32-bit version of Windows 7 running on the other.