There’s no legitimate free Windows 11 product key, but most people don’t need one. If your PC already runs a licensed copy of Windows 10 or Windows 11, it likely has a digital license, and Windows 11 activates automatically. Eligible Windows 10 PCs can also still upgrade to Windows 11 for free. Check Settings > System > Activation to see your status.
Avoid key-generator sites, cheap “lifetime” keys from unknown sellers, and activation scripts. They can break Microsoft’s license terms, can stop working without warning, and some carry malware.
Check Whether Windows Is Already Activated
- Press Windows key + I to open Settings.
- Select System, then Activation.
- Look at Activation state. If it says Active, you don’t need a product key.
Windows activated with a digital license stays activated after you reinstall Windows on the same PC, as long as you install the same edition, such as Home or Pro.
Upgrade From Windows 10 for Free
Microsoft still offers Windows 11 as a free upgrade for Windows 10 PCs that meet the hardware requirements. Microsoft’s Get Windows 11 page notes that the free upgrade is for the same edition you have on Windows 10, so Windows 10 Home becomes Windows 11 Home.
- On your Windows 10 PC, open Settings and select Update & Security.
- Select Windows Update, then Check for updates.
- If your PC is eligible, select Download and install under the Windows 11 upgrade offer.
- Follow the prompts and let the PC restart. Your license carries over, so you won’t be asked for a key.
No offer showing up? Your PC may not meet the requirements. Our guide on how to update to Windows 11 from Windows 10 covers the PC Health Check app and the Installation Assistant.
Legal Ways to Use Windows 11 Without Paying
- Digital license: most PCs sold with Windows already include one. Reinstalling or upgrading on the same hardware keeps it.
- Link your Microsoft account: if you change hardware, like replacing the motherboard, a digital license linked to your Microsoft account can help. Use the Troubleshoot option on the Activation page, as Microsoft explains in its activation troubleshooter guide.
- School or work: many schools and employers provide Windows licenses. Ask your IT department.
What Happens If You Don’t Activate Windows 11
Windows 11 installs and runs before it’s activated, so you can set it up first and buy a key later. Until you activate, expect these limits:
- An “Activate Windows” watermark in the lower-right corner of the screen.
- Personalization settings, such as wallpaper, colors, themes, and the lock screen, are locked.
- Reminders to activate in Settings.
Security updates still install, but Microsoft’s license terms expect you to activate with a valid license, so treat an unactivated copy as temporary.
Find the Product Key Built Into Your PC
Many laptops and desktops that shipped with Windows have a key stored in the firmware. Windows reads it automatically during setup, but you can view it if you need it:
- Right-click the Start button and select Terminal.
- Paste the command below and press Enter.
(Get-CimInstance -Query "select * from SoftwareLicensingService").OA3xOriginalProductKey- If a 25-character key appears, that’s your PC’s original key. If nothing appears, your PC uses a digital license instead, and you don’t need a key.
Buy and Enter a Key Safely
If you do need a key, buy Windows 11 Home or Pro from the Microsoft Store or an authorized retailer. Then enter it:
- Open Settings > System > Activation.
- Select Upgrade your edition of Windows to expand it.
- Select Change next to Change product key.
- Type the 25-character key and select Next, then Activate.
Prefer the command line? See how to activate Windows 11 with Command Prompt.
Frequently Asked Questions
Is it illegal to use Windows 11 without activating it?
Windows 11 will run without activation, with some limits, but Microsoft’s license terms expect a valid license, so treat an unactivated copy as a temporary step. Using keys that weren’t sold legitimately violates those terms. (This isn’t legal advice.)
Can I use my Windows 10 key for Windows 11?
Often, yes. A valid Windows 10 key for the same edition usually activates Windows 11, and PCs upgraded from licensed Windows 10 activate on their own.
What about the free “generic” Windows 11 keys listed online?
Those are usually generic keys, like the KMS client keys Microsoft publishes for businesses. Microsoft says KMS client keys need a KMS server on a company network and won’t activate a retail copy of Windows. They let you install an edition, but they won’t activate your PC.
Is the Windows 11 free upgrade still available?
Yes. Microsoft still lists Windows 11 as a free upgrade for eligible Windows 10 PCs, for the same edition you already have.
Matthew Burleigh has been writing tech tutorials since 2008. His writing has appeared on dozens of different websites and been read hundreds of millions of times.
After receiving his Bachelor’s and Master’s degrees in Computer Science he spent several years working in IT management for small businesses. However, he now works full time writing content online and creating websites.
His main writing topics include iPhones, Microsoft Office, Google Apps, Android, and Photoshop, but he has also written about many other tech topics as well.