Without a product key being labelled, is there is any way to identify what Microsoft software product a given product key is meant to activate?

Let's say for example I had the product key ABCDE-FGHIJ-KLMNO-PQRST-UVWXY, but I had no clue if was meant for Windows 7 Ultimate, Windows 7 Home Premium, Vista Ultimate, or even Office 2010. Is there a way I could identify the software product the key is meant for (or at least get a good estimate)?

Note: I have searched and searched many times on the Internet, but the only results I ever find are how to recover a lost product key by using something like Nirsoft ProduKey. This is not what I am looking for.

  • 1
    I recall that when XP first came out, there was a tool (“blue-list” iirc), that had a key-validation function for different editions of XP and Office. However, I think I remember reading that later on (e.g., after SP1 or 2), some valid keys would no longer validate because Microsoft had changed the algorithm.
    – Synetech
    Dec 9, 2012 at 4:27
  • From user BWhite: support.microsoft.com/en-us/contactus has a link to a chat bot which answers the question, which product is this license key for, or, why isn't my key working?
    – fixer1234
    Sep 13, 2018 at 3:39

6 Answers 6


Unfortunately there isn’t. The product key sequence is according to a mathematical algorithm. The product key is a partially random, 25-character alphanumeric code, specifically designed to defeat against keygens and leaked serial numbers. The code has three (known) components:

  1. An actual serial number
  2. Verification data (using modular math)
  3. A checksum (CRC) for typos

There are several good references to how product keys are utilized. This one is particularly good.

  • If I have 90% of the product key, but some of the digits are faded away from the sticker, is there a way to figure out what the remaining digits are? Oct 9, 2021 at 22:50

Yes, you can determine which Microsoft Product ID (PID) a given key corresponds to with tools like Microsoft PID Checker (alternative) and The Ultimate PID Checker (alternative). The former supports a wide array of products, including Windows 7/2008 R2 - 10/2016, Office 2010-2016, Visual Studio, Exchange Server, and more, while the latter includes support for Windows XP/2003 - 8/2012 and Office 2010-2013.

While you do need to select the right general product (e.g., Windows 7) in order to get the specific version information (e.g., Windows 7 Ultimate Retail), it only takes a moment to try them all if you've lost even that information:

Microsoft PID Checker screenshot

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  • "Microsoft PID Checker" worked perfect for me, I had a couple of worn-down Windows 7 COA stickers, so the validity checking allowed me to trial-and-error the missing digits, along with some angled light to reflect off the surface of the stickers (even if the ink is gone, the indent is usually still present, and will give you a decent idea of what letter/number was there). Sep 9, 2022 at 23:39

VAMT 2.0 allows administrators to automate and centrally manage a range of activities related to Windows client, Windows Server, and Office 2010 activations.

To see what it looks like and how to make it work, check out this link


I would contact Microsoft themselves about this, I don't know of any tool or method for end users like us to do this. The other option is to install, preferably in a virtual machine, all the possible software that it could belong to and see which one "takes" it.


I know this may be a little late, but I had the same issue tonight and found this thread. I can't speak to identifying Windows Product Keys, but Microsoft does have a site where you can enter a product key and it will identify the version of office the key belongs to.

Here is the link: https://products.office.com/en-us/microsoft-office-2013

It will take some guess work, but under the Office 2013 Resources heading on that page, you can select the version you think the key is for. Once selected, you may have to log into your Microsoft account. Then, follow the instructions, which includes entering the product key. It will ID the Office software, year and provide instruction for download.

Very simple. I hope this helps.

  • 2
    Your link doesn't seem to be valid anymore. It's just information about Office 365. May 9, 2018 at 15:13

Go to https://www.microsoft.com/en-us/software-download/office and enter the product key , It will give you the version number and option to download

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