OS is an abbreviation for the word Operating System. An Operating System is the software that tells a computer how to operate. It controls hardware, executes programs, manages tasks and resources, and provides the user with an interface to the computer.

Windows

• Windows 10 & 11 - Click Start (windows logo), Settings-> System-> About, Look under Windows Specifications to find out your version and edition of Windows.
• Windows 8.1 or Windows Server 2012 R2 - Swipe in from the right edge of the screen, tap Settings, and then tap Change PC settings. (If you're using a mouse, point to the lower-right corner of the screen, move the mouse pointer up, click Settings, and then click Change PC settings.). Next, Tap or click PC and devices, and then tap or click PC info. Look under Windows for the version and edition.

• Windows 8 or Windows Server 2012 - On the Start screen, type Computer, press and hold or right-click Computer, and then tap or click Properties. Then look under Windows edition for the version.

• Windows 7 and Windows Server 2008 R2 - Click Start or the Windows logo right click Computer then click Properties. Look in System.

• Windows Vista and Windows Server 2008 - Click Start or the Windows logo depending on what you have then click Control Panel->System and Maintenance->System.

  You could also try Clicking Start or the Windows logo then if you have a "Start Seach" field type winver then Double-click winver.exe from the results. If you had a run box instead of search just click Run type winver click OK.

• Windows NT, Windows 2000, Windows XP and Windows Server 2003 - Click Start -> RunType winver then click OK. You could also try typing msinfo32 or sysdm.cpl or winmsd if you like. Lastly you might try typing dxdiag. Windows might prompt you to verify drivers click No.

• Windows 95/98/ME - Click Start-> Settings->Control Panel double-click System click General tab. Locate version number under system heading.

• Windows CE - Click StartSettings Control Panelclick the System applet. If that does not work you might just have to look in the General Tab or somewhere in the System Tab.

  You can also find out if your computer is running a 32-bit or 64-bit version of Windows in the same areas listed above.

Macintosh

• OS X/Mac OS X/macOS - Click the Apple menu at the top of your screen then click About this Mac. To get more detailed information after that click More Info -> Software. Note: Apple has changed the name of its OS a few times in recent years. It went from OS X to Mac OS. Then in 2016 changed Mac OS X to just macOS.

• iOS (iPhoneOS) - On your iPhone touch the Settings icon (looks like a gear) -> General -> About. Look under version. Note: Apple has changed the name of it's OS to iOS from iPhoneOS.

Linux

• Open a terminal program (get to a command prompt) and type uname -a. This will give you your kernel version, but might not mention the distribution your running. To find out what distribution of linux your running (Ex. Ubuntu) try lsb_release -a or cat /etc/*release or cat /etc/issue* or cat /proc/version.

FreeBSD/NetBSD/OpenBSD/DragonFlyBSD

• Open a terminal program (get to a command prompt) and type uname -a. This will tell you the version (release) and type of BSD your running.

Android Phone

• Go to the Home Screen (push the home button or just keep pressing the left facing triangle (back button)). Then push the Applications button (looks like little squares or like 3 colons :::). Find and touch the Settings icon. Scroll to the bottom of the list. then touch About Phone. Look for lines that say Firmware version or Android version.

Blackberry (RIM OS)

• Go to the Options menu and choose About. If that does not work try the Tools icon then click on Settings then About.

Solaris (SunOS)

• Open a terminal program (get to a command prompt) and type uname -a or for lots of info (on newer Solaris machines) type showrev -a.

AIX

• Open a terminal program (get to a command prompt) and type oslevel -r or uname -a or lslpp -h bos.rte.

IOS (Cisco)

• On the command line in enabled mode (enable) type show version.

XOS (Extreme Networks)

• On the command line at an administrator privilege level type show version.

IronWare OS (Foundry)

• On the command line at an administrator privilege level type show version or possibly cf version.

OpenVMS

• At a terminal propt type show system /noprocess

Windows

• Follow the instructions above in the What's the version of my OS? section to find out if your OS is 32-bit or 64-bit. The page with the version info usually has something that says if it is 32-bit or 64-bit. Only Windows XP and later could possibly be 64-bit. If you don't see something that says "64-bit" somewhere on the version page, it is likely you have a 32-bit version of Windows.

Macintosh

• Mac OS X - Click About this Mac from the Apple menu at the top of your screen. Then click More Info -> Software.

  Mac OS X 10.5 (or greater) can run 64-bit applications. Any processor that says: Intel Core 2 Duo, Intel Xeon, or PowerPC G5 are 64-bit processors. All currently shipping Macs ship with OS X and a 64-bit processor. 10.6 still boots a 32-bit kernel by default. It's possible to boot at 64-bit kernel. Read all about it here.

Linux

• Open a command prompt and type uname -a. If you see x86_64 or ia64 then your OS is 64-bit. If you see i386 or i486 or i586 or i686 then your OS is 32-bit.

OpenBSD/FreeBSD/NetBSD

• Open a command prompt and type uname -a. If you see amd64 then you are running a 64-bit OS. If you see i386 your running a 32-bit OS.

Solaris (SunOS)

• Open a command prompt and type isainfo -v. This will show you if your OS is capable of running 32-bit and 64-bit applications. If that does not work you can try typing uname -a. This will show you the version of Solaris your using. All versions after 5.7 are 64-bit compliant.

  Sun's platforms transitioned to 64-bit over a period of time, which makes identifying the platform for 64-bit compliance tricky.

AIX

• Open a command prompt and type getconf -a | grep KERN. If that does not work try bootinfo -K. Also, try looking at some libraries by typing file /usr/lib/boot/unix*. If you see mention of 64-bit then the OS is 64-bit capable.

OpenVMS

• If you are on VAX hardware, it is a 32-bit OS, otherwise it is a 64-bit OS

Black magic. Just kidding. When you visit a site with your web browser it sends a little nugget of information to that site called a "User Agent". The user agent has a few minor pieces of information about your browser, platform, and OS version. Using this information a guess can be made about what Operating System your using.

Why is it a guess? The user agent your browser sends to the website can be changed very easily. It's not to be trusted in any way, shape, or form as the truth, but most people generally use browsers who's user agents have not been changed.

Why is it only generally? Sometimes the people that provide your internet access will modify this user agent so the website can not tell what your browser is or will set the user agent to a general browser type so the site will render the same for everyone. This is not the norm so don't fret to much.

Most browsers do not put the version number of the OS in the user agent string but some do. Apple products are a good example. The browsers that put OS version information in the user agent string are usually the browsers come with the OS or are created (compiled) by the vendor. The vendors built-in browser will provide the most information to this site for it to render the most accurate guess. For example Apple's built-in browser Safari provides the full version of the OS in the user agent string, but Firefox on the same Apple computer only provdes a portion of the version number.

First, read the section called "How do you know what my OS is?". Now that you know how we go about guessing your OS you might have an idea on why we can't. The most likely answer is that there might not be enough information in your user agent string to render a good guess or since the user agent is so easily changed yours could have been changed to something that is not normal or is so obscure that a guess could not even be rendered. It's a good chance it's nothing you did so don't worry. Go through the "What's the version of my OS" section above and see if you notice anything mentioned there. It's likely you have an idea what OS your using your just not sure.

Guessing an Operating System by just using a user agent is not as easy as it looks. There are so many little differences between each one. Words are not always in the same spot. Some things are spelled differently. The list goes on and on. This site is constantly being monitored, updated, and tweaked to fix errors. If it got your OS incorrect one day come back later and it might be correct in the future. If your OS was guessed incorrectly submit your user agent and your correct os to o|s|1|@|w|h|a|t|s|m|y|o|s|.|c|o|m (remove |'s). It will be looked into and if possible fixed.

The most recent problem with trying to guess an OS through the user agent is that major browsers have started to cap the version of the OS given by the browser. This means most version information is now going to be useless for many Operating Systems like Windows 11 or the most recent versions of macOS. Now more then ever your going to have to rely on the instructions above to verify your Operating System.

Microsoft decided that they would share OS user agent versions between multiple desktop and server releases of their Operating Systems. That means there are some server and desktop user agents look almost exactly the same. It is possible that you are using a server version of Windows, but very unlikely if you are just a regular home user. Usually if your running Windows server you know it. Use the ways above to help you verify your Windows version.

In Microsoft's infinite wisdom they have decided to share user agent versions between Windows 10 and 11. Which means now you really should check your versions in the instructions above, and not rely on this site telling you if your running Windows 10 or 11. Thanks M$.

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