How to Find Microsoft Office Product Keys

Use a key finder program to locate your lost Microsoft product key

Most software programs require a product key as part of the installation process, including all recent versions of Microsoft Office. If you've lost your Microsoft Office product key, you'll need to find it before you can reinstall the software suite.

Microsoft Office product keys are encrypted inside the Windows Registry, so searching for them manually is nearly impossible. You'll find a string of numbers once you locate the correct registry key, but what you'll find is encrypted text, not a working Office product key you can enter.

Fortunately, programs called key finders do the finding and decrypting for you, giving you your valid, paid-for Office product key — that missing puzzle piece so you can successfully reinstall the program.

Person holding a keyring at a desk with an Office box and computer monitor on it
Lifewire / Miguel Co

If you don't find your key while using one of the methods outlined below, the only legal option you have left is to buy a brand new copy of MS Office. As often as you may come across free product keys for Office, or key generator programs, neither are good ways to go about this.

Microsoft Office 2019 & 2016 & 2013

The Microsoft Office 2019, 2016, and 2013 product key situation is unique compared to older versions of Office (below).

Screenshot of a document in Microsoft Word 2013
Microsoft Office 2013 (Word).

Unfortunately for us, only the last five characters of the 25-character Office 2019, Office 2016, or Office 2013 product key is stored on your computer, making a product key finder pretty much useless in this case.

I know, right away I'm going back on some of the stuff I said above! For whatever reason, Microsoft completely changed how they handled product keys with these newer versions of MS Office

Of course, this unfortunate fact doesn't change the reality that you still need that product key to reinstall either version.

If you have an installed version of Microsoft Office 2019, 2016, or 2013 via your Office 365 subscription, you don't need to worry about product keys. Just sign in to your account and download and install the latest version of Office to your computer.

It's not all bad news that key finder programs are no longer helpful with these versions of Office. In fact, the new way that Microsoft is handling Office keys might not be such a bad thing after all.

Microsoft Office 2010 & 2007

Like all versions of Office, Microsoft Office 2010 and Microsoft Office 2007 both require a unique product key during the installation process.

Screenshot of a document in Microsoft Word 2010
Microsoft Office 2010 (Word).

If you're sure that you no longer have the physical product key for your version of Microsoft Office, or you've lost or deleted the email receipt that included the product key in it, you might, as you read in the introduction above, be able to extract the key from the registry using a key finder tool.

LicenseCrawler, the key finder program we recommend for Office 2010 & 2007 product keys in that tutorial, will find your product key in just seconds.

Older Versions of Microsoft Office

Older versions of Microsoft Office, like Office 2003 (2003), Office XP (2001), Office 2000 (1999), and Office 97 (1996) all also require product keys during installation.

Screenshot of a document in Microsoft Word 2002
Microsoft Office XP (Word 2002).

Considering how old some of these versions of Microsoft Office are, it'd be surprising if anyone still has the product key around.

The Office 2010/2007 tutorial above could be used for any of these versions of Office as well, but we've found that Keyfinder Thing, the key finder tool we recommend in this tutorial, does a better job with these older suites.