How to find your Windows or Office product key
Reinstalling Windows or moving to a new PC? Here's where your product key is, and when you don't need one at all.
Updated 7 October 202601Check your purchase email or account
If you bought a key, it's in the email you received after paying. Search your inbox for the store's name or for "product key". If you bought from SOS License, every key is also saved in your account, under your orders.
02You may not need a key: digital licenses
Once Windows 10 or 11 is activated, Microsoft remembers that PC. If you reinstall Windows on the same PC, choose I don't have a product key during setup and Windows activates itself when it goes online.
To keep that license if you later change hardware, link it to your Microsoft account: open Settings > System > Activation and sign in with a Microsoft account.
03Find the key built into a laptop or prebuilt PC
Most PCs sold with Windows have the original key stored in the firmware. Open PowerShell and run:
(Get-CimInstance -ClassName SoftwareLicensingService).OA3xOriginalProductKey
If it shows a key, that's the edition your PC came with, usually Windows Home. If it shows nothing, your PC didn't come with a stored key.
04See which key is installed now
Windows never shows the full installed key, but you can see its last 5 characters to match it with a key you have. Open Command Prompt and run:
slmgr /dli
A window shows the edition, the last 5 characters of the key and the activation status.
05Office product keys
Office doesn't show your full key after activation either. Look in your purchase email or account first. To see the last 5 characters of the installed Office key, open Command Prompt as administrator and run:
cscript "C:\Program Files\Microsoft Office\Office16\OSPP.VBS" /dstatus
Office 2021 and Office 2024 also use the Office16 folder. If you have 32-bit Office, replace Program Files with Program Files (x86).
06Avoid "key finder" downloads
Many free "product key finder" programs come bundled with adware or worse. The built-in commands above are all you need.
07Lost your key and can't find it anywhere?
If the PC was activated before, try reinstalling without a key first (step 2). If it still won't activate, you'll need a new key: Windows 11 Pro, Windows 11 Home or Office 2024 Professional Plus. Then follow how to activate Windows.
