GPT-5.6 now powers Microsoft 365 Copilot across productivity apps
OpenAI's GPT-5.6 is now the default model in Microsoft 365 Copilot, delivering faster results across Word, Excel, PowerPoint, Chat, and a new collaborative Cowork feature.
OpenAI announced this week that GPT-5.6 is now the preferred model powering Microsoft 365 Copilot across Word, Excel, PowerPoint, Chat, and a new collaborative feature called Cowork. The company says the upgrade delivers faster and higher-quality results for enterprise users working across Microsoft's productivity suite.
The timing invites scrutiny. Industry observers have speculated about the depth of the OpenAI-Microsoft partnership as OpenAI pursues its own consumer products and Microsoft develops in-house alternatives. The GPT-5.6 rollout suggests the commercial relationship remains active, though neither company has addressed broader partnership questions. OpenAI's announcement emphasized performance gains in document generation, spreadsheet analysis, and presentation design but did not publish benchmark comparisons against GPT-4 or earlier GPT-5 versions.
Cowork appears to be a new collaborative workspace within the Copilot interface, though OpenAI provided no technical detail on how it differs from the existing Chat tab. A key open question remains whether GPT-5.6 is a full model release or a tuned variant of an existing GPT-5 checkpoint. OpenAI has not published a standalone model card, API endpoint, or pricing tier for GPT-5.6 outside the Microsoft integration. Watch for whether this version surfaces in ChatGPT or the OpenAI API in coming weeks—that would signal whether GPT-5.6 is a Microsoft-exclusive optimization or the start of a broader rollout.
