To register for free, the only verified "free" method is through the 30-day full-featured trial provided by the official developer, ExtendOffice .

To check your trial status: After installation, open Excel, click on the tab, then click License in the ribbon. It will show the number of days remaining.

Choose the version that matches your Microsoft Office bitness (32-bit or 64-bit). You can verify this in Excel by going to . Install the Software Close all Microsoft Office applications.

Any website claiming to provide a "working free key" falls into one of three categories:

This is Excel’s most powerful built-in tool. It handles data cleaning, merging sheets, and transforming tables—functions that Kutools is famous for.

, and enter your email address to begin the 30-day trial period. Microsoft Learn Verified Pricing and Terms

If you later purchase a license, navigate to the tab. Select Help (or Register ) and click Register .