To find your Windows product key, you can check the registry using a script, use a third-party tool like ProduKey, or check your email or receipt. First, for the registry method: open Notepad, paste the provided script, save it as productkey.vbs, and run it to display your key in a message box—note this works only on activated Windows. Second, use ProduKey from NirSoft: download the tool, run it without installation, and it will show keys for all installed Microsoft products. Third, check your email inbox, spam folder, order history on Microsoft’s website, or physical packaging if you bought a retail copy. Additionally, if upgraded from a previous version, sign into account.microsoft.com and check under “Services & subscriptions” for your key linked to your Microsoft account.

If you need to find your Windows product key—maybe for a reinstall, moving to a new drive, or just keeping a backup—it’s not always obvious where to look. The good news is there are reliable ways to retrieve it without too much hassle.

Check the Registry (Works on Activated Windows)

Windows stores your product key in the registry, but it’s encoded. You can’t just copy-paste it directly, but you can use a script or tool to decode and display it.

Here’s how:

• Open Notepad and paste the following script:

Set WshShell = CreateObject("WScript.Shell")
 MsgBox ConvertFromKey(WshShell.RegRead("HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DigitalProductId"))

Function ConvertFromKey(Key)
    Const KeyOffset = 52
    Dim isWin8, Maps, i, j, Current, KeyOutput, LastKeyPartCount

    isWin8 = (Key(66) \ 6) And 1
    Key(66) = (Key(66) And &HF7) Or ((isWin8 And 1) * 4)
    Maps = "BCDFGHJKMPQRTVWXY2346789"
    For i = 24 To 0 Step -1
        Current = 0
        For j = 14 To 0 Step -1
            Current = Current * 256
            Current = Key(j   KeyOffset)   Current
            Key(j   KeyOffset) = Current \ 24
            Current = Current Mod 24
        Next
        KeyOutput = Mid(Maps, Current   1, 1) & KeyOutput
        LastKeyPartCount = LastKeyPartCount   1
        If LastKeyPartCount = 5 Then
            LastKeyPartCount = 0
            If i <> 0 Then KeyOutput = "-" & KeyOutput
        End If
    Next
    ConvertFromKey = KeyOutput
End Function

• Save the file as productkey.vbs
• Double-click the file – a message box will show your product key

Note: This method only works if Windows is already activated.

Use a Free Third-Party Tool

If scripting isn’t your thing, several free tools can quickly show your Windows product key. One of the more trusted options is ProduKey from NirSoft.

What to do:

• Download ProduKey from the official NirSoft website
• Run the tool (no installation needed)
• It will immediately display the product keys for all installed Microsoft products, including Windows

Warning: Always download from the official site to avoid fake versions with malware. Don’t run these tools on untrusted machines or public computers.

Look at Your Email or Receipt (For Purchased Licenses)

If you bought Windows directly—either as a digital license or boxed software—you should have received a confirmation email or receipt that includes the product key.

Check:

• Your inbox (and spam/junk folder) for emails from Microsoft or your reseller
• Order history on Microsoft’s website or wherever you made the purchase
• Physical packaging if you bought a retail copy

Tip: If you upgraded from a previous version, your new key might be linked to your Microsoft account. Sign in to account.microsoft.com and check under “Services & subscriptions.”

That’s about it. Depending on your situation—whether Windows is activated, whether you’re comfortable with scripts—you’ve got options. Some methods work better than others depending on your setup, but one of these should get you what you need.

The above is the detailed content of How to find my Windows product key?. For more information, please follow other related articles on the PHP Chinese website!