Learn how to find a Windows product key for activation, and when you'll use a digital license instead.

A product key is a 25-character code that's used to activate Windows and helps verify that Windows hasn't been used on more PCs than the Microsoft Software License Terms allow.

If your purchase of Office or Microsoft 365 came with a product key, you enter your product key on one of the websites listed below for your product. After you enter your key, you can download and install …

If you paid for a Microsoft 365 product to be included on your new Windows PC, a digital product key is transmitted to your PC when you activate Windows. You won't receive a printed product key.

Learn how to activate Windows using a product key or digital license, check your activation status, and link your Microsoft account.

Get help with product key errors, or geographical region errors, when you redeem a new Office product key on Office.com/setup.

Many tasks for Office products don't require a product key because your Microsoft account takes care of them instead.

In summary, a product key is used during installation, while an activation code is used to activate the software afterwards. Both are essential for ensuring a legitimate and functional software experience.

Get your product key. If you used a product key to get to Windows 11, then you’ll need that key again after the hardware change. To find out how to locate your key, see Find your Windows product key. …

Find the software, and then select Product key/Install. Note: If you're having problems installing an app from the Microsoft Store, see Fix problems with apps from Microsoft Store. If you're looking for …