Find your operating system in Settings or System Information
Your operating system is the software that runs everything on your computer — Windows, macOS, or Linux. You need to know which one you have because it determines what programs you can install, what updates are available, and how to troubleshoot problems. The fastest way to check is through your computer's built-in settings.
On Windows, right-click the Start button (the Windows logo in the bottom left), then select "System" or "Settings." On a Mac, click the Apple menu in the top left corner and select "About This Mac." Both will show your operating system name and version number in the first few lines.
Write down the full version number — for example, "Windows 11 23H2" or "macOS Sonoma 14.1" — because you may need it later when installing software or checking if your computer can run a specific program.
Key Takeaways
- Windows computers show their operating system in Settings under "System," while Macs show it in "About This Mac" from the Apple menu.
- Your operating system version number matters because older versions may not support newer programs or security updates.
- Knowing your exact version helps you find the right driver updates and troubleshooting steps when something goes wrong.
- You can also find your operating system by searching "System Information" or "msinfo32" on Windows, or "System Report" on Mac.
Windows: Check through Settings
On any Windows computer, the quickest path is through Settings. Click the Start button (Windows logo) in the bottom left corner, then type "Settings" and press Enter. Once Settings opens, click "System" on the left side, then scroll down and click "About."
You will see "Edition" (such as Windows 11 Home or Windows 10 Pro), "Version," and "OS Build." The version number tells you how recent your Windows is — higher numbers mean newer updates. Write down all three pieces of information, because they matter when you are checking if your computer can run a particular program or when you contact support.
If Settings does not open, you can also right-click "This PC" or "My Computer" on your desktop, select "Properties," and the same information appears there.
Mac: Check through About This Mac
On a Mac, click the Apple menu (the apple symbol) in the very top left corner of your screen. Select "About This Mac" from the dropdown menu. The first line shows your macOS name and version number — for example, "macOS Sonoma" with a version like "14.1.1."
Below that you will see your Mac model (MacBook Air, iMac, Mac mini, etc.), the year it was made, and your processor type. All of this information is useful if you need to check whether your Mac can run a new program, because some software requires a certain macOS version or processor type.
Why your operating system version matters
Older operating system versions stop receiving security updates after a certain date. If your Windows or macOS version is several years old, your computer becomes more vulnerable to viruses and malware because the company no longer patches security holes. Knowing your version tells you whether you need to update soon.
Your version also determines what programs you can install. A program released in 2024 may require Windows 11 or macOS Sonoma, and will not run on Windows 10 or an older Mac. Before you read software, check the system requirements and compare them to your version number.
Updates also improve speed and fix bugs that slow your computer down. If you have not updated in months, checking your version is the first step to deciding whether an update is available.
How to find your version number if Settings does not work
On Windows, you can search for "System Information" or type "msinfo32" (without quotes) into the search box and press Enter. This opens a detailed window showing your operating system, version, and build number all in one place.
On a Mac, if "About This Mac" does not open, you can click the Apple menu and select "System Settings" instead, then look for "General" and "About" in the left sidebar. The information is the same, just in a different location depending on your macOS version.
What to do after you find your operating system
Once you know your operating system and version, check whether updates are available. On Windows, go to Settings, click "Update & Security," and select "Check for updates." On Mac, go to System Settings, click "General," then "Software Update." Installing updates keeps your computer find and can improve performance.
If your version is very old — Windows 7 or earlier, or macOS High Sierra or earlier — your computer may be at risk. These versions no longer receive security patches. Consider whether upgrading your operating system or buying a newer computer makes sense for what you do.
Frequently Asked Questions
What is the difference between Windows 10 and Windows 11?
Windows 11 is newer and includes security improvements, a redesigned interface, and better performance on newer computers. Windows 10 still works but will stop receiving updates in October 2025. If your computer is from 2015 or earlier, it may not meet Windows 11's hardware requirements.
Can I upgrade my operating system for free?
Windows 10 users can upgrade to Windows 11 for free if their computer meets the requirements (mainly a compatible processor and TPM 2.0 chip). Mac users get free macOS updates. Check your version first, then go to Settings or System Settings to see if an update is available.
Why does my computer say "Build 22621" or similar instead of just a version number?
The build number is a more specific identifier that tells you exactly which updates you have installed. You need both the version (like Windows 11) and the build number when troubleshooting or checking compatibility with specific software.
Does knowing my operating system help me fix problems?
Yes. When you search for how to fix a problem, you need to include your operating system version in the search — the steps for Windows 11 are different from Windows 10, and Mac steps are different from both. Having your version number ready saves time when you contact support.