What's the Difference Between 32-Bit and 64-Bit?

In the computer world, 32-bit and 64-bit refer to the type of central processing unit, operating system, driver, software program, etc., that utilizes that particular architecture.

You've probably seen the option to download a piece of software as a 32-bit version or a 64-bit version. The difference does, in fact, matter because the two were programmed for separate systems.

What Do They Mean?

• 32-bit hardware and software are often referred to as x86 or x86-32.
• 64-bit hardware and software are often referred to as x64 or x86-64.
• 32-bit systems utilize data in 32-bit pieces, while 64-bit systems utilize data in 64-bit pieces. In general, the more data that can be processed at once, the faster the system can operate.

There are several other advantages to a 64-bit system, most practically the ability to use significantly greater amounts of physical memory (more than the 4 GB allowed by a 32-bit machine).

A 64-bit processor can handle 64 bits of data at once, which allows it to compute information faster regardless of the processor's clock speed. It allows for more memory usage because, with 32-bit processors, only 2³² addresses of RAM can be accessed (all 32-digit binary numbers).

This restriction means the processor uses a much lower amount of memory than 64-bit processors, which can read double the digits. In fact, with every additional digit, the maximum number of addresses that can be accessed doubles, too, allowing for much more memory than a 32-bit processor.

With 64-bit processors having a larger bit size and therefore the ability to calculate bigger numbers, the computer also ends up dealing with everything at a much more precise level than a 32-bit computer. Pixels on your screen, for example, can be colored and placed more accurately than pixels on a 32-bit computer.

64-Bit and 32-Bit Operating Systems

Most new processors are based on the 64-bit architecture and support 64-bit operating systems. These processors are also fully compatible with 32-bit operating systems.

All editions of Windows 11 are 64-bit only, and most editions of Windows 10, Windows 8, Windows 7, and Windows Vista are available in 64-bit format. Of the editions of Windows XP, only Professional is available in 64-bit.

All editions of Windows, from XP up to 10, are available in 32-bit.

Every Mac operating system since v10.8 (Mountain Lion) has been 64-bit.

Like Windows, Linux can be 32-bit or 64-bit. You can see which you're running with the lscpu command.

Not Sure if the Copy of Windows on Your PC Is 32-Bit or 64-Bit?

The quickest and easiest way to see if you're running a 32-bit or 64-bit version of Windows is to check what it says in Control Panel. Another simple method is to check the Program Files folder; there's more information on that below.

To see the hardware architecture, open Command Prompt and enter this command:

 echo %PROCESSOR_ARCHITECTURE%

You might get a response like AMD64 to indicate that you have a x64 based system, or x86 for 32-bit.

This is another command that works by checking for information in the HKLM registry hive:

 reg query "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v PROCESSOR_ARCHITECTURE

That command should result in much more text, but then end with a response like one of these:

 PROCESSOR_ARCHITECTURE REG_SZ x86
PROCESSOR_ARCHITECTURE REG_SZ AMD64

Why It Matters

Knowing the difference is crucial so you're installing the right kinds of software and device drivers. For example, when given the option between downloading a 32-bit or 64-bit version, a 64-bit software program is the better choice. However, it won't run at all if you're on a 32-bit version of Windows.

One notable difference for you, the end-user, is that it's possible that after downloading a large program, you'll find that you've wasted that time since it won't run on your specific computer. For example, if you've downloaded a 64-bit program that you expect to use on a 32-bit OS.

However, some 32-bit programs can run just fine on a 64-bit system. In other words, 32-bit programs are compatible with 64-bit operating systems. That rule, however, isn't always valid, and that's especially the case with some device drivers since hardware devices require the exact version to be installed for it to interface with the software (i.e., 64-bit drivers are necessary for a 64-bit OS, and 32-bit drivers for a 32-bit OS).

Another time when 32-bit and 64-bit differences come into play is when troubleshooting a software issue or looking through a program's installation directory.

It's important to realize that 64-bit versions of Windows have two different install folders, since they also contain a 32-bit directory. However, a 32-bit version only has one install folder. What's confusing is that the 64-bit version's Program Files folder is the same name as the 32-bit Program Files folder on a 32-bit version of Windows.

One example of why this is the case is so a 32-bit program doesn't try to use a 64-bit DLL, which won't work. Instead, when a 32-bit program installs in the 32-bit Program Files folder, and then you run said program, Windows knows that it needs to pull up some 32-bit specific files instead of those used for 64-bit programs.

I understand this is a bit confusing. Take a look at these folders for some clarity:

64-bit versions of Windows have two folders:

• 32-bit location: C:\Program Files (x86)\
• 64-bit location: C:\Program Files\

32-bit version of Windows have one folder:

• 32-bit location: C:\Program Files\

As you can tell, it's not really true to plainly say that the 64-bit Program Files folder is C:\Program Files\ since that's not true for a 32-bit OS.

Beyond how-tos and instructionals that require you to know the difference, another reason understanding these terms is important is if you're not sure if you should get a 64-bit computer or 64-bit program.

For example, maybe you want a video editing program to have access to larger amounts of RAM than what it could use on a 32-bit system. Or, if you know that a piece of hardware you use doesn't have a 64-bit driver option, then you know you can't use it with a 64-bit computer. The same is true for old 16-bit applications that might not work on a 64-bit computer; knowing this can help you decide if you should switch to a 64-bit computer or stick to 32-bit.