A Product Key is a commonly unique, alphanumeric code of any length required by Microsoft Office programs during installation. They help software developers ensure that every copy of their software has been legally purchased.
Most software, including some of the most popular software makers’ operating systems and programs, require product keys. As a general rule these days, if you pay for software like Microsoft Office, you probably need a product key when you install it.
In addition to the product keys, some software companies, including Microsoft, often require a product code to help ensure that software is legally purchased.
Open source and free software programs typically do not require a product key unless the manufacturer uses it for statistical purposes.
Note: Product keys are also sometimes referred to as CD keys, key codes, licenses, software keys, product codes, or installation keys.
How Product Keys Are Used
A product key functions similarly to a program’s password. This password is provided when you purchase the software and can only be used with that application. The software will most likely not open past the product key page without the product code, or it will run but only as a trial of the full version.
Product keys are typically only valid for the one-time installation of the system, but some product key servers allow the same key to be used by an unlimited number of people if they are not used concurrently.
In these cases, there are only a limited number of product key slots available, so if the software that was using the key is closed, another can be opened and use that same slot.
Microsoft Product Keys
Microsoft Windows OS versions, as well as all versions of Microsoft Office and most other Microsoft retail programs, require the entry of unique product keys during the installation process.
Microsoft product keys are frequently found on product key stickers. Product keys in most versions of Windows and other Microsoft software are 25 characters long and contain both letters and numbers.
Product keys are of the five-by-five set (25-character xxxxx-xxxxx-xxxxx-xxxxx-xxxxx.) format used in all versions of Windows since Windows 98, including Windows 10, Windows 8, Windows 7, Windows Vista, and Windows XP.
Older versions of Windows, such as Windows NT and Windows 95, had 20-character product keys that looked something like this: xxxxx-xxxxx-xxxxx-xxxxx. To enter Office product key visit www.office.com/setup.
Author: Jace Mrazz is a Microsoft Office expert with 5 years of experience in the technology industry. He has written technical and SEO blogs, white papers, and reviews for a variety of websites including office.com/setup and office365.com/setup.