Check your operating system in three clicks

Your operating system is the software that runs your computer — Windows, macOS, or Linux. You need to know which one you have because different programs only work on certain systems, and troubleshooting steps differ by system. Finding out takes less than a minute and requires no special knowledge.

The fastest way depends on whether you use Windows or a Mac. Both systems hide this information in plain sight, in a settings menu you probably have not opened before. Once you know your system, you also need to know the version number — Windows 10 and Windows 11 are different, and the same is true for macOS versions. The version number matters because some programs and updates only work on newer versions.

Key Takeaways

  • Windows users can find their system by right-clicking "This PC" on the desktop or in File Explorer and selecting Properties.
  • Mac users can click the Apple menu in the top-left corner and select "About This Mac" to see their operating system and version.
  • Your operating system version number matters — Windows 10 and Windows 11 require different updates, and older Macs may not run newer software.
  • Write down both your system name and version number, because you will need both when troubleshooting or installing new programs.

Finding your operating system on Windows

On Windows, the quickest path is through "This PC." Look at your desktop or open File Explorer (the folder icon on your taskbar). Right-click on "This PC" in the left sidebar or on the desktop, then select "Properties" from the menu that appears. A window will open showing your system information.

Look for the line that says "System" or "Edition." This tells you whether you have Windows 10, Windows 11, or an older version. Below that, find "Version" — this is a number like 22H2 or 21H2. Write both down. You will also see "Build," which is a longer number; you do not need this for most purposes, but some troubleshooting steps ask for it.

If you cannot find "This PC" on your desktop, open the Start menu (the Windows logo in the bottom-left corner), type "system information," and click the first result. The same information appears there.

Finding your operating system on a Mac

On a Mac, click the Apple menu (the symbol) in the top-left corner of your screen. Select "About This Mac" from the dropdown menu. A window opens when ready showing your system information.

Look for the line labeled "System Software" or "macOS." This tells you the name and version — for example, "macOS Sonoma 14.1" or "macOS Ventura 13.5." The first word is always "macOS" (on newer Macs) or "OS X" (on older ones). The name after that — Sonoma, Ventura, Monterey — is the version name. The number after the name is the version number. Write down both the name and the number.

If you see "OS X" instead of "macOS," your computer is older. This matters because some newer programs will not run on older versions of OS X.

Understanding version numbers and what they mean

Version numbers matter more than you might think. A program that runs on Windows 11 may not run on Windows 10. The same is true for Macs — software written for macOS Sonoma may not work on macOS Monterey. When you read a program or follow troubleshooting steps online, the instructions often say "for Windows 10" or "for macOS 13 and later." If your version is older, the steps may not work.

Windows version numbers look like "22H2" or "21H2." The "H" stands for "half-year," so "22H2" means the second update released in 2022. You do not need to understand this — just know that a higher number is newer. If a program says it needs version 22H2 and you have 21H2, you may need to update Windows first.

macOS version numbers work the same way. "macOS Sonoma 14.1" is newer than "macOS Ventura 13.5." If a program requires Sonoma and you have Ventura, you cannot install it without upgrading your entire operating system.

What to do after you find your operating system

Once you know your system and version, write it down somewhere you can find it later — a note on your phone, a sticky note on your monitor, or a document on your desktop. You will need this information when you read programs, follow troubleshooting guides, or contact technical support.

If you are looking for a specific program and the website says it requires a newer version than you have, you have two choices: update your operating system, or use a different program that works on your version. Updating takes time and sometimes requires a restart, but it is usually free. Before you update, check that your computer has enough storage space — updates need several gigabytes of free room.

Checking if your operating system is up to date

Knowing your version number is the first step. The second is checking whether you are running the latest version available for your system. On Windows, open Settings (the gear icon), select "System," then "About." Scroll down and look for "Windows Update." If it says "You are up to date," you have the latest version. If it offers an update, click "read and install."

On a Mac, click the Apple menu, select "System Settings" (or "System Preferences" on older Macs), then look for "General" and "Software Update." If an update is available, click "Update Now." Your Mac will restart during the process, so save your work first.

Updates are free and usually improve security and fix problems. They take 15 minutes to an hour depending on your internet speed and how much your computer has to change. Do not turn off your computer during an update — let it finish, even if it restarts several times.

Frequently Asked Questions

What if I see "Windows 10" but the version number looks different than my friend's?

Both of you have Windows 10, but you are on different update versions. This is normal — Microsoft releases updates throughout the year, and not every computer gets them at the same time. As long as you both have Windows 10, most programs will work on both computers. The version number only matters if a program specifically requires a certain version.

Can I change my operating system from Windows to Mac?

Not without buying a new computer. Your operating system is built into your computer's hardware. A Windows computer cannot run macOS, and a Mac cannot run Windows (with rare exceptions involving special software). If you want to switch, you need to buy a computer that comes with the system you want.

Why does my Mac say "OS X" instead of "macOS"?

Apple changed the name from OS X to macOS in 2016. If you see "OS X," your Mac is older than that. You can still use it, but some newer programs may not work on it. Check the version number — if it is OS X 10.15 or older, many current programs will not run.

Do I need to update my operating system right away?

Not when ready, but you should update within a few weeks. Updates fix security problems that hackers can exploit, so waiting too long puts your computer at risk. Set aside an hour when you do not need your computer, save your work, and let the update run without interruption.

What if my computer is too old to get the latest operating system?

Older computers sometimes cannot run the newest versions because they do not have enough memory or processing power. Check your system information — it will tell you the newest version your computer can run. You can still use your computer with an older version, but some new programs will not work on it. Consider what programs you actually need before deciding whether to upgrade.