Where to find your serial number on Windows, Mac, and Linux

Your computer's serial number is a unique identifier printed or etched on your device and also stored in your system. On Windows, you can find it through System Information or by running a command. On Mac, it appears in About This Mac under System Report. On Linux, the location depends on your manufacturer, but you can often retrieve it through the terminal.

The serial number is not the same as your product key or device name. It identifies your specific physical machine, which matters when you need warranty service, file insurance claims, or report a device as lost or stolen. Manufacturers use serial numbers to track when a device was made and which components it contains.

Key Takeaways

  • On Windows, open System Information by pressing Windows key + R, typing msinfo32, and looking for "System Serial Number" in the window that opens.
  • On Mac, click the Apple menu, select About This Mac, click System Report, and find the serial number listed under Hardware Overview.
  • You can also find the serial number printed on a sticker on the bottom or back of your laptop, or inside the battery compartment on some older models.
  • Keep your serial number in a safe place — you will need it for warranty claims, repairs, or if your device is stolen.

Finding the serial number on Windows

The fastest way on Windows is through System Information. Press the Windows key and R at the same time to open the Run dialog. Type msinfo32 and press Enter. A window titled System Information will open. Look for the field labeled "System Serial Number" — this is your computer's unique identifier.

If System Information does not show the serial number, try the command line instead. Press Windows key + R, type cmd, and press Enter to open Command Prompt. Type the command wmic bios get serialnumber and press Enter. The serial number will appear on the next line.

Some manufacturers also print the serial number on a sticker attached to the bottom or back of your laptop. If you are looking at a desktop computer, check the back panel or the side of the case. Older laptops sometimes have the serial number inside the battery compartment — you may need to remove the battery to see it.

Finding the serial number on Mac

On Mac, the serial number is easiest to find through System Report. Click the Apple menu in the top-left corner, then select About This Mac. A window will open showing basic information about your computer. Click the button labeled System Report. A larger window will open with detailed hardware information.

In System Report, look for the section called Hardware Overview. The serial number appears as "Serial Number (system)" in that section. You can also find it printed on the bottom of your MacBook or on the back of an iMac or Mac mini.

If you prefer the terminal, you can also retrieve the serial number by opening Terminal (found in Applications > Utilities) and typing the command system_profiler SPHardwareDataType | grep "Serial Number". The serial number will appear in the output.

Finding the serial number on Linux

Linux does not have a single standard location for serial numbers the way Windows and Mac do, because Linux runs on many different hardware manufacturers' machines. The method depends on whether you built your computer, bought a pre-built system, or are using a laptop from a specific manufacturer.

For most systems, open a terminal and try the command sudo dmidecode -s system-serial-number. This queries your system's BIOS or UEFI firmware for the serial number. You may need to enter your password. If that does not work, check the physical sticker on your device — the serial number is usually printed there.

If you are using a laptop from a major manufacturer like Dell, Lenovo, or HP, you can also check their support websites. Many manufacturers let you enter your serial number to look up warranty information and driver downloads.

What to do with your serial number once you have it

Write down or screenshot your serial number and store it somewhere safe — a notes app, a password manager, or a physical notebook. You will need it if your computer breaks and you want to claim warranty service. Manufacturers use the serial number to verify when your device was made and whether it is still under coverage.

If your computer is stolen, the serial number is the most reliable way to prove ownership. Police reports and insurance claims both ask for it. Some manufacturers can remotely disable stolen devices if you report the serial number to them, though this varies by brand.

You should also keep your serial number handy if you sell your computer. Buyers sometimes want to verify the device's history or check remaining warranty before purchase. Having the number ready makes the transaction faster.

Serial number versus other identifiers

Your serial number is different from your product key, device name, and MAC address — three other identifiers you might see on your computer. The product key (or license key) is a code that proves you own a copy of Windows or other software. The device name is the nickname your computer goes by on your network — you can change it anytime. The MAC address is a code that identifies your network card, not your whole computer.

Only the serial number uniquely identifies your physical machine from the factory. It cannot be changed, and it is the one manufacturers use to track warranty and ownership. When someone asks for your serial number, they are asking for proof of which specific device you own, not proof that you own a copy of Windows.

Frequently Asked Questions

Can I change my computer's serial number?

No. The serial number is burned into your computer's firmware or motherboard during manufacturing. Changing it is not possible through normal means and would void your warranty. If someone tells you they can change your serial number, they are either mistaken or offering an illegal service.

What if System Information or the terminal command does not show a serial number?

Some computers, especially older ones or custom-built machines, may not have a serial number stored in the system. Check the physical stickers on your device — the manufacturer usually prints it there. If you still cannot find it, contact the manufacturer's support with your device model number.

Is my serial number the same as my device ID?

No. Your device ID is a code Windows generates to identify your computer on the network. Your serial number is what the manufacturer assigned when the device was built. They are different codes that serve different purposes.

Do I need my serial number to get technical support?

Most manufacturers ask for it, especially if you are claiming warranty service or reporting a problem. Having it ready speeds up the process. Some support teams can look up your device history and warranty status once they have the serial number.

What should I do if I lose my computer?

Report the serial number to the police and to your insurance company if you have coverage. Contact the manufacturer with the serial number — some can flag the device so it cannot be activated on their services. If you stored the serial number in a cloud backup or password manager, you can still access it even if the physical device is gone.