If you're preparing to reinstall a program or an operating system (like a clean install of Windows), you'll need to find your unique product key (CD key) or serial number before continuing.

Windows key extractor free download - XP CD Key Extractor, Magic Key Extractor, Windows Product Key Viewer/Changer, and many more programs. Windows key extractor free download - XP CD Key.

Normally this product key is located on the original install disc, or maybe in your order confirmation email. If you've lost your product key, you can often find it in the Windows Registry but this can be difficult, or sometimes even impossible, to do. Fortunately, there are many free key finder programs available to help.

Please read our Key Finder Programs FAQ for lots of helpful information. This isn't an easy topic, especially if you're new to it.

Today we will see how a simple VBS script can be used to show us the product key of an installed copy of Windows 10, Windows 8 or Windows 7. It is a simple solution to extract your product key from the OS installed on your PC without using any third party software. To use, put the hard drive in a working machine (must also be Windows 2000, XP, Vista, Windows 7 or Windows 8) or use Windows PE (not tested, should work) and click Load Hive. Then point it to the dead Windows install. If you're using Windows Vista, Administrator rights are required for this feature. Typically you can find your Microsoft Windows product key on a sticker attached to your PC. Use Magical Jelly Bean Keyfinder to extract the CD keys for software you currently have installed. We show you how to find your Windows product key in any version of Windows. Find your Windows 10 product key. You might be able to extract your Windows 10 product key using ProduKey.

Below are the top 21 free key finder programs. We also keep a list of commercial key finder programs but it's highly recommended that you exhaust the options below before paying for one.

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Belarc Advisor

What We Like

Finds keys for newer versions of Windows
Also locates MS Office keys
Shows other information about your computer
Very small download size
Lets you copy information to the clipboard

What We Don't Like

Can't be used portably (you have to install it)

Belarc Advisor is the standard when it comes to system information software. I've been using this program for many, many years. One small aspect of Belarc Advisor is its ability to extract product keys for many software programs, including the one for Windows.

Advantages include a display of information in your browser window, no adware/toolbars to worry about, and an extensive list of other important computer data.

Finds Keys for Operating Systems:Windows 10, Windows 8 & 8.1, Windows 7, Windows Vista, Windows Server 2012/2008/2003, Windows XP, Windows 2000, Windows NT, Windows ME, Windows 98, and Windows 95.

Finds Keys for Other Software:Microsoft Office 2013, 2010, (plus all previous versions), Microsoft enterprise products, most programs from Adobe, Nero, Corel, and more, as well as keys for popular video games.

Please try Belarc Advisor for your software and Windows key finding needs before any other program. It's likely to provide you with the best results.

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Magical Jelly Bean Keyfinder

What We Like

Very simple interface that's easy to understand
Will find your Windows 10 key as well as keys for older OSs
The product keys are listed automatically so you don't have to click anything
Product keys can be saved to a file or copied to the clipboard
Includes advanced features like the option to view remote product keys

What We Don't Like

Doesn't find keys for newer MS Office programs
The program is sometimes identified as a virus in antivirus programs
Setup tries to install other, unrelated programs along with MJB Keyfinder

The Magical Jelly Bean Keyfinder program is a free utility that retrieves product keys from the registry. It also has the ability to find product keys for Microsoft Office programs, along with product keys from many other non-Microsoft programs.

Advantages include very small size, ease of use, instant display of product keys, and multiple product key saving options.

Finds Keys for Operating Systems: Windows 10, Windows 8, Windows 7, Windows Vista, Windows Server 2003, Windows XP, Windows 2000, Windows ME, Windows 98, and Windows 95.

Finds Keys for Other Software: Microsoft Office 2007, Office 2003, Office XP, and several non-Microsoft programs.

The Magical Jelly Bean Keyfinder website says that this free key finder will find your Office 2010 product key but in fact, it does not, at least as of v2.0.10.13.

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Winkeyfinder

What We Like

Very easy to use
Finds keys for Windows and Microsoft Office
Works as a portable program
You can save the results or print them off
Lets you change product keys in some operating systems
Shows results instantly

What We Don't Like

Unable to locate the MS Office 2016 product key
Some of the advanced options might be confusing if you're new to key finders

The Winkeyfinder program is another free utility that retrieves product keys from the Windows registry.

Advantages include small program size, no installation required, and additional features such as the ability to change registered user information.

Finds Keys for Operating Systems: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, Windows 2000, Windows ME, and Windows 98.

Finds Keys for Other Software: Microsoft Office 2013, 2010, 2007, 2003, XP, 2000 SP2, and 97.

Although the program doesn't state that it supports MS Office 2016, and so, therefore, shouldn't be expected to, that is one of the only Microsoft-related product keys that Winkeyfinder will not find.

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Keyfinder Thing

What We Like

Installs quickly
Provides a very minimal and easy-to-understand interface
Shows keys for Windows, MS Office, and other programs
You can export the keys to save them to a file

What We Don't Like

Shows a key for Windows 10 and 8 but it isn't correct
Setup might try to install an unnecessary program
Loads slower than other key finder programs

Keyfinder Thing is another free, easy to use utility that finds product keys and serial numbers hidden in the Windows registry.

Advantages include small program size, nothing to run, and support for a large list of non-Microsoft programs.

Finds Keys for Operating Systems: Windows 7, Windows Vista, Windows 2003 Server, Windows XP, Windows 2000, and Windows ME.

Finds Keys for Other Software: Microsoft Office 2007, Office 2003, Office XP, Microsoft Money, Nero, Corel Suite, The Sims, and many more programs.

Keyfinder Thing doesn't find the right product keys for Windows 10, Windows 8, or Windows NT, even though one may show up in the results. I tested it in Windows XP and didn't find issues.

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Product Key Finder

What We Like

Finds keys for Windows 7 and older OSs
Uncluttered and minimal UI couldn't be easier to use
Lets you export the product keys to a file
You can also find keys from a registry file

What We Don't Like

Doesn't show Windows 10/8 product keys
Setup might attempt to install another program to your computer
Includes zero advanced features (which you may or may not want depending on what you plan to do)

The not-so-originally-named Product Key Finder tool is actually a pretty good key finder program.

After executing Product Key Finder, a simple window opens displaying your Windows product key along with other product keys and serial numbers that Product Key Finder can locate.

Windows Serial Extractor