If cost is the reason you searched for "Office 365 KMS," consider these legitimate free alternatives:
While “Microsoft Office 365 KMS” is a misnomer, KMS remains a robust, low-bandwidth activation solution for volume-licensed Microsoft Office (2019, 2021, 2024 LTSC). Organizations migrating to true Microsoft 365 should abandon KMS entirely and adopt cloud-based subscription activation. For those maintaining on-premises, perpetual Office deployments, KMS offers predictable, offline-capable activation after an initial 5-client threshold is met.
The most critical thing to understand is that (the subscription version) and Office LTSC/Volume License (the "one-time purchase" version) use entirely different activation methods.
: When a user installs a volume-licensed version of Office, the software is pre-configured with a Generic Volume License Key (GVLK). It then searches the network (usually via DNS) for the KMS host. Activation
Uses User-Based Activation . Users sign in with their work or school account. The software periodically "calls home" to Microsoft's cloud to verify the subscription status.