AI tool privacy · Comparison
Gemini vs Microsoft Copilot: how each handles your data
By David Michaelson, MS Last checked October 23, 2026
The short answer
Gemini
In a Google Workspace business account, Gemini does not use your content to train models outside your organization without permission; on a personal Google Account, Google uses your chats to improve its AI, with help from human reviewers, while Keep Activity is on.
Microsoft Copilot
Microsoft 365 Copilot at work does not use your prompts, responses, or files to train its foundation models; the free personal Copilot app lets you opt out of model training and keeps conversations for 18 months by default.
For a team: compare the plan you would actually buy, not just the brand. The tables below show each plan’s answers, with sources.
Side by side
Every answer links to the vendor’s own page and shows the date we read it. Where we could not confirm an answer, the cell says so in plain words and links to the page we checked.
| Question | GeminiPersonal Google Account | Microsoft CopilotCopilot app, personal Microsoft account |
|---|---|---|
| Trains on your data by default? | Yes, while Keep Activity is on. Google says it uses your activity to provide, develop, and improve its services, including training generative AI models. With Keep Activity off, future chats are not used to train its AI models unless you send feedback. Read on October 23, 2026 Source: support.google.com | You can opt out. Microsoft says you control whether it can use your conversations to train its generative AI models, and you can opt out at any time. Read on October 23, 2026 Source: support.microsoft.com |
| How long your data is kept | With Keep Activity on, activity is deleted after 18 months by default. You can choose 3 or 36 months, or not to auto-delete. With it off, chats are kept for 72 hours. Chats read by human reviewers are kept up to 3 years, even after you delete your activity. Read on October 23, 2026 Source: support.google.com | 18 months by default. Files you share are kept no longer than 18 months and then deleted automatically. Read on October 23, 2026 Source: support.microsoft.com |
| Who can see it | The privacy hub does not describe company access to a personal account. It says human reviewers, including trained reviewers from Google’s service providers, read some chats, and asks you not to enter confidential information you would not want a reviewer to see. Read on October 23, 2026 Source: support.google.com | Not described on the page we read. Page checked: support.microsoft.com, October 23, 2026 |
| Where data is stored | Not stated on the privacy hub we read. Page checked: support.google.com, October 23, 2026 | Not stated on the page we read. Page checked: support.microsoft.com, October 23, 2026 |
| How to delete | Review and delete chats in Gemini Apps Activity at myactivity.google.com/product/gemini. Chats a reviewer has already read are not deleted and are kept up to 3 years. Read on October 23, 2026 Source: support.google.com | Delete one conversation, or your entire conversation history, at any time from your conversation history. Read on October 23, 2026 Source: support.microsoft.com |
| Question | GeminiGoogle Workspace (business accounts) | Microsoft CopilotMicrosoft 365 Copilot (work account) |
|---|---|---|
| Trains on your data by default? | No, not without your permission. Google says your content is not reviewed by humans or used to train generative AI models outside your organization without permission. Read on October 23, 2026 Source: support.google.com | No. Microsoft says prompts, responses, and data accessed through Microsoft Graph are not used to train its foundation models. Optional feedback may be used to improve Copilot, and admins can manage it. Read on October 23, 2026 Source: learn.microsoft.com |
| How long your data is kept | Set by your admin. In the Gemini app, up to 36 months. In Gmail, Docs, and other Workspace apps, 90 days to indefinite. With conversation history off, new chats are kept for up to 72 hours. Read on October 23, 2026 Source: support.google.com | Prompts and responses are stored with your organization’s other Microsoft 365 content. Admins can set retention policies for Copilot chats in Microsoft Purview. Read on October 23, 2026 Source: learn.microsoft.com |
| Who can see it | Admins get audit logs that track user activity and interactions with Gemini, and they control whether conversations are saved and for how long. Read on October 23, 2026 Source: support.google.com | Admins can view and manage stored prompts and responses with Content search or Microsoft Purview. Read on October 23, 2026 Source: learn.microsoft.com |
| Where data is stored | Not stated for Gemini chats on the page we read. Page checked: support.google.com, October 23, 2026 | For EU customers, Copilot is an EU Data Boundary service. Customers outside the EU may have their queries processed in the US, the EU, or other regions. Read on October 23, 2026 Source: learn.microsoft.com |
| How to delete | Users can delete conversations themselves unless an admin turns that off. Read on October 23, 2026 Source: support.google.com | Each person can delete their Copilot activity history, including prompts and responses, in the My Account portal. Read on October 23, 2026 Source: learn.microsoft.com |
Building your own approved tools list? The SafeStart Handbook includes one, with company accounts and safer privacy settings.