As you may be finding out, perhaps half way through reinstalling Windows 8, you must have your product key to continue the installation. Windows 8, as well as most operating systems and other software, require the entry of unique product keys, or sometimes serial numbers, during installation.
Your Windows 8 product key should be with the email confirmation you received after buying Windows 8 for download, or with your packaging if you purchased it in a retail package. If Windows 8 came preinstalled on your computer, your product key should be on a sticker on your computer or with your documentation.
Fortunately, if you can't find documentation of your Windows 8 product key, you may be able to extract it from the Windows Registry using a program called a product key finder.
Follow the steps below to find your Windows 8 product key using one of these tools.
Important: A product key finder program will only find your valid Windows 8 key if Windows 8 is installed and working, and if you've manually entered the Windows 8 product key in some previous installation. See my Windows Product Keys FAQ and Key Finder Programs FAQ pages for more information.
Time Required: Finding your Windows 8 product key should take less than 15 minutes
Applies To: You can find your Windows 8 or Windows 8.1 product key this way no matter what edition of Windows 8 you're using.
Download Belarc Advisor, a free PC audit program with full Windows 8 support that also functions as a key finder tool. Unfortunately, manually locating the Windows 8 product key in the registry isn't possible so you'll need to use a program like this.
See my List of Free Key Finder Programs for more tools like Belarc Advisor but please try it first since I've confirmed that it correctly finds Windows 8 product keys.
Note: Any product key finder that advertises support for Windows 8 will work for either edition: Windows 8 or Windows 8 Pro, and very likely both editions of Windows 8.1.
- Install Belarc Advisor, following whatever instructions are given during the installation.
Note: If you choose a different keyfinder, please know that some are supported by optional add-on programs so be sure to uncheck those options during the program's installation if you don't want them. A few of them require no installation at all.
- Run Belarc Advisor (the initial analysis may take a little while) and note the Windows 8 product key displayed in the Software Licenses section.
The Windows 8 product key is a series of 25 letters and numbers and should look like this: xxxxx-xxxxx-xxxxx-xxxxx-xxxxx.
- Write down the Windows 8 key exactly as shown for use when reinstalling Windows 8.
Important: Make sure each and every letter and number is written exactly as shown. If even one digit isn't transcribed correctly, the key won't work to reinstall Windows 8.
- If you need to install Windows 8 but wasn't successful finding your Windows 8 product key with a product key finder program, you have two more choices:
You can request a replacement product key from Microsoft or you can purchase a new copy of Windows 8.1, which will of course come with a new and valid product key.
Requesting a replacement Windows 8 product key is going to be much more cost effective than buying an entirely new copy of Windows 8, but you may have to do that if the replacement doesn't work out.