When you need to reinstall Windows or move to a new PC, you'll need your product key — but the email receipt and sticker may be long gone. Fortunately, you can retrieve the key from your running Windows installation using a few built-in commands or a free tool. This guide covers the Command Prompt and PowerShell methods, the best free key-extraction tools, and what to do when none of these work.
Table of Contents
- What Is a Windows Product Key?
- Find the Key Using Command Prompt
- Find the Key Using PowerShell
- Find the Key with a Free Tool
- What to Do When You Can't Find the Key
- FAQ
- Summary
What Is a Windows Product Key?
A Windows product key is a 25-character alphanumeric string (five groups of five characters) used to activate Windows as a genuine licensed copy. It may be required when reinstalling Windows or migrating to a new PC.
Product Key vs. Digital License
Since Windows 10, Microsoft also uses digital licenses — a different activation method that's becoming increasingly common.
- Product key — a 25-character string. Issued with boxed retail and OEM/DSP editions
- Digital license — tied to your Microsoft account. Common on Windows 10/11 preinstalled PCs and upgrade installations
With a digital license, signing into your Microsoft account during reinstallation activates Windows automatically — no product key needed.
Keys You Can Extract vs. Keys You Can't
The key you can pull from your PC is the one currently being used for activation. The OEM key — embedded in the BIOS/UEFI by the manufacturer — can be read with a command. A retail key entered manually after purchase is stored encrypted in the registry and requires a dedicated tool to read.
Find the Key Using Command Prompt
This is the simplest method, and it works for OEM-edition Windows with a BIOS-embedded key.
- Type cmd in the Start menu
- Right-click Command Prompt and select Run as administrator
- Run this command:
wmic path softwarelicensingservice get OA3xOriginalProductKey
- If a 25-character key appears, you're done
If nothing appears, your PC uses a digital license or the key isn't embedded in the BIOS. Try the PowerShell method or a dedicated tool instead.
Note: The wmic command is deprecated in some versions of Windows 11. Learning the PowerShell method as a backup is a good idea.
Find the Key Using PowerShell
PowerShell can retrieve the same BIOS-embedded key and is the recommended method on Windows 11.
- Type powershell in the Start menu
- Right-click Windows PowerShell and select Run as administrator
- Run this command:
(Get-WmiObject -query 'select * from SoftwareLicensingService').OA3xOriginalProductKey
- If a key appears, copy and store it somewhere safe
This also works in PowerShell 7 (pwsh), but the built-in Windows PowerShell is the most reliable environment.
If the result is empty, your current Windows is activated with a digital license or a separately entered retail key — not a BIOS-embedded OEM key.
Find the Key with a Free Tool
To retrieve a retail key stored in the registry, you'll need a dedicated tool.
ShowKeyPlus
An open-source tool available through the Microsoft Store and GitHub.
- Search for ShowKeyPlus in the Microsoft Store and install it
- Launch the app
- The screen shows both the Installed Key (currently active) and the OEM Key (BIOS-embedded)
If the installed key and OEM key differ, the PC was likely upgraded with a retail key on top of the original OEM installation. ShowKeyPlus also lets you copy keys to the clipboard or save them to a text file — handy for keeping a record.
ProduKey
A long-running key extraction utility from NirSoft. It also extracts keys for Microsoft 365 and other Microsoft products.
- Download ProduKey from the NirSoft official site
- Extract the ZIP and run ProduKey.exe
- A list of product keys for all installed Microsoft software appears
Some antivirus programs may flag ProduKey as a "potentially unwanted program" because of its key-reading behavior. Download only from the official NirSoft site, and remove it after use if you prefer.
What to Do When You Can't Find the Key
If no method above produces a usable key, here are the alternatives.
Check Your Microsoft Account License
If your PC uses a digital license, you don't need a product key at all:
- Sign in at account.microsoft.com
- Go to Devices and select your PC
- View the license status
During reinstallation, simply click I don't have a product key and proceed. After signing into the same Microsoft account, Windows activates automatically.
Check Purchase History and Email
For retail or OEM purchases, check these locations:
- Microsoft account order history
- Purchase confirmation email (search for "product key" or "Product Key" in the subject)
- For boxed retail: the card inside the box or a sticker on the packaging
- For DSP editions: the card sleeve that came with the disc
- For OEM PCs: the COA certificate sticker on the case or underside of the laptop
Physical stickers can fade over time. If your PC is new, photograph the COA sticker now and save it to cloud storage.
FAQ
Q. Can I use a product key on multiple PCs?
A. Retail and OEM/DSP keys are licensed for one PC at a time — using the same key on multiple machines simultaneously violates the license terms. You can reinstall on the same PC as many times as you like. Some products like Microsoft 365 Family allow multiple device activations.
Q. What happens if I lose my product key?
A. If your PC uses a digital license linked to a Microsoft account, reinstalling Windows will activate it automatically as long as you sign in with the same account. Otherwise, contact your retailer or, as a last resort, purchase a new license.
Q. The command shows "BBBBB-BBBBB-BBBBB-BBBBB-BBBBB" or similar repeating characters.
A. This pattern appears on PCs where no key is embedded in the BIOS — typically custom-built PCs or retail-upgrade installations. Use ShowKeyPlus to check the currently active installed key instead.
Q. Are these free tools safe to use?
A. ShowKeyPlus is distributed through the Microsoft Store, so it's been through Microsoft's review process. For tools like ProduKey, download from the official site only and run a virus scan after downloading to be sure.
Q. Is it safe to share my product key with others?
A. A product key isn't personally identifiable information, but since licenses are typically tied to one PC, sharing it violates the license agreement. Don't post screenshots of your product key on social media or forums.
Summary
The fastest way to find your Windows product key is the Command Prompt command wmic path softwarelicensingservice get OA3xOriginalProductKey. On Windows 11, use the PowerShell equivalent: (Get-WmiObject -query 'select * from SoftwareLicensingService').OA3xOriginalProductKey. For retail keys stored in the registry, ShowKeyPlus is the safest option. If your PC uses a digital license, you don't need a product key at all — just sign in with your Microsoft account during reinstallation and activation happens automatically. Check and record your key right after setting up a new PC so you have it ready when you need it.
