Serial number

Updated: 07/31/2022 by Computer Hope
Serial number on HP computer

Sometimes abbreviated as Serial No., SN, S/N, or SNID, a serial number is a unique number used for identification and inventory purposes. A serial number allows a company to identify a product and get additional information about it for replacement or to find compatible parts. Pictured is an example of what a serial number may look like on the back or side of a computer.

Serial No. 4CE0460D0G
Model No. p6774y

Despite the name, a serial number often contains letters and numbers. How many characters make up a serial number differs greatly, depending on the manufacturer, product, and model. Most serial numbers have at least six or seven characters, and some serial numbers have twenty or more.


Some manufactures (e.g., Acer) may have both a serial number and an SNID on their devices. However, usually either number would work when calling technical support.

Locating serial numbers

Hardware - A serial number for a hardware device is often on the bottom or back of the device.


With computers running Microsoft Windows or macOS, you can also find the hardware serial number of a computer through System or System Information.

Software - Software serial numbers, also known as product identification numbers and CD keys, may be accessible by logging into the software website with a verified user account. They may also be listed on the software's physical packaging or a CD/DVD jewel box.

Business terms, Computer abbreviations, Hardware terms, Model number, No, Serial key, Version