xAI has released Grok, an artificial intelligence add-in for Excel available on the Microsoft Marketplace. While the add-in itself is free to install, it requires an active subscription to one of Grok's paid tiers (SuperGrok, Heavy, Business, or Enterprise). The tool operates through a sidebar interface where users can submit requests for web searches, spreadsheet modifications, and financial model creation—tasks the company claims its latest version handles effectively.

Grok arrives in a competitive landscape already dominated by Microsoft's deeply integrated Copilot and Google's Gemini, which may limit its appeal to users without existing Grok subscriptions. Testing revealed immediate usage limits requiring plan upgrades, and Grok's integration depth lags behind Microsoft's COPILOT cell-level function. Additional hesitation stems from security considerations highlighted by Microsoft's warning that the add-in can read and modify documents whilst transmitting data across the internet, coupled with documented incidents where Grok Build previously uploaded entire code repositories to external servers and produced outputs later acknowledged as problematic.