Check the product key on the original packaging or card
Look for a sticker on the PC or laptop
Open Command Prompt as administrator
Enter: wmic path softwarelicensingservice get OA3xOriginalProductKey
Check your Microsoft account for a digital license
Go to Settings
Select Update & Security
Open Activation
Verify activation status
Use a third-party key finder tool if needed
Check your email receipt if you bought Windows online
Contact the device manufacturer or retailer
If Windows was preinstalled, the key may be embedded in the BIOS/UEFI