Using ChatGPT or other AI tools? Here’s who can see your chat history

While AI tools like ChatGPT and Google Gemini can be helpful, they’re also potential privacy minefields.

Most AI assistants save a complete record of your conversations, making them easily visible to anyone with access to your devices. Those conversations are also stored online, often indefinitely, so they could be exposed due to bugs or security breaches. In some cases, AI providers can even send your chats along to human reviewers.

All of this should give you pause, especially if you plan to share your innermost thoughts with AI tools or use them to process personal information. To better protect your privacy, consider making some tweaks to your settings, using private conversation modes, or even turning to AI assistants that protect your privacy by default.

To help make sense of the options, I looked through all the privacy settings and policies of every major AI assistant. Here’s what you need to know about what they do with your data, and what you can do about it:

ChatGPT

By default: ChatGPT uses your data to train AI, and warns that its “training data may incidentally include personal information.”
Can humans review your chats? OpenAI’s ChatGPT FAQ says it may “review conversations” to improve its systems.
Can you disable AI training? Yes. Go to Settings > Data controls > Improve the model for everyone.
Is there a private chat mode? Yes. Click “Turn on temporary chat” in the top-right corner to keep a chat out of your history and avoid having it used to train AI.
Can you share chats with others? Yes, by generating a shareable link. (OpenAI launched, then removed, a feature that let search engines index shared chats.)
Are your chats used for targeted ads? OpenAI’s privacy policy says it does not sell or share personal data for contextual behavioral advertising, doesn’t process data for targeted ads, and doesn’t process sensitive personal data to infer characteristics about consumers.
How long does it keep your data? Up to 30 days for temporary and deleted chats, though even some of those may be kept longer for “security and legal obligations.” All other data is stored indefinitely.

Google Gemini

By default: Gemini uses your data to train AI.
Can humans review your chats? Yes. Google says not to enter “any data you wouldn’t want a reviewer to see.” Once a reviewer sees your data, Google keeps it for up to three years—even if you delete your chat history.
Can you disable AI training? Yes. Go to myactivity.google.com/product/gemini, click the “Turn off” drop-down menu, then select either “Turn off” or “Turn off and delete activity.”
Is there a private chat mode? No, but turning Gemini Apps Activity off will hide your chat history from the sidebar. (Note, however, that re-enabling it without deleting past data will bring your history back.)
Can you share chats with others? Yes, by generating a shareable link.
Are your chats used for targeted ads? Google says it doesn’t use Gemini chats to show you ads, but the company’s privacy policy allows for it. Google says it will communicate any changes it makes to this policy.
How long does it keep your data? Indefinitely, unless you turn on auto-deletion in Gemini Apps Activity.

Anthropic Claude

By default: Anthropic doesn’t use conversations to train AI unless you report them manually or opt in to testing new features.
Can humans review your chats? No, though Anthropic reviews conversations flagged as violating its usage policies.
Can you disable AI training? Not applicable.
Is there a private chat mode? No. You must delete past conversations manually to hide them from your history.
Can you share chats with others? Yes, by generating a shareable link.
Are your chats used for targeted ads? Anthropic doesn’t use conversations for targeted ads.
How long does it keep your data? Up to two years, or seven years for prompts flagged for trust and safety violations.

Microsoft Copilot

By default: Microsoft uses your data to train AI.
Can humans review your chats? Yes. Microsoft’s privacy policy says it uses “both automated and manual (human) methods of processing” personal data.
Can you disable AI training? Yes, though the option is buried. Click your profile image > your name > Privacy and disable “Model training on text.”
Is there a private chat mode? No. You must delete chats one by one or clear your history from Microsoft’s account page.
Can you share chats with others? Yes, by generating a shareable link. Note that shared links can’t be unshared without deleting the chat.
Are your chats used for targeted ads? Microsoft uses your data for targeted ads and has discussed integrating ads with AI. You can disable this by clicking your profile image > your name > Privacy and disabling “Personalization and memory.” A separate link disables all personalized ads for your Microsoft account.
How long does it keep your data? Data is stored for 18 months, unless you delete it manually.

xAI Grok

By default: Uses your data to train AI.
Can humans review your chats? Yes. Grok’s FAQ says a “limited number” of “authorized personnel” may review conversations for quality or safety.
Can you disable AI training? Yes. Click your profile image and go to Settings > Data Controls, then disable “Improve the Model.”
Is there a private chat mode? Click the “Private” button at the top right to keep a chat out of your history and avoid having it used to train AI.
Can you share chats with others? Yes, by generating a shareable link. Note that shared links can’t be unshared without deleting the chat.
Are your chats used for targeted ads? Grok’s privacy policy says it does not sell or share information for targeted ad purposes.
How long does it keep your data? Private Chats and even deleted conversations are stored for 30 days. All other data is stored indefinitely.

Meta AI

By default: Uses your data to train AI.
Can humans review your chats? Yes. Meta’s privacy policy says it uses manual review to “understand and enable creation” of AI content.
Can you disable AI training? Not directly. U.S. users can fill out this form. Users in the EU and U.K. can exercise their right to object.
Is there a private chat mode? No.
Can you share chats with others? Yes. Shared links automatically appear in a public feed and can show up in other Meta apps as well.
Are your chats used for targeted ads? Meta’s privacy policy says it targets ads based on the information it collects, including interactions with AI.
How long does it keep your data? Indefinitely.

Perplexity

By default: Uses your data to train AI.
Can humans review your chats? Perplexity’s privacy policy does not mention human review.
Can you disable AI training? Yes. Go to Account > Preferences and disable “AI data retention.”
Is there a private chat mode? Yes. Click your profile icon, then select “Incognito” under your account name.
Can you share chats with others? Yes, by generating a shareable link.
Are your chats used for targeted ads? Yes. Perplexity says it may share your information with third-party advertising partners and may collect from other sources (for instance, data brokers) to improve its ad targeting.
How long does it keep your data? Until you delete your account.

Duck.AI

By default: Duck.AI doesn’t use your data to train AI, thanks to deals with major providers.
Can humans review your chats? No.
Can you disable AI training? Not applicable.
Is there a private chat mode? No. You must delete previous chats individually or all at once through the sidebar.
Can you share chats with others? No.
Are your chats used for targeted ads? No.
How long does it keep your data? Model providers keep anonymized data for up to 30 days, unless needed for legal or safety reasons.

Proton Lumo

By default: Proton Lumo doesn’t use your data to train AI.
Can humans review your chats? No.
Can you disable AI training? Not applicable.
Is there a private chat mode? Yes. Click the glasses icon at the top right.
Can you share chats with others? No.
Are your chats used for targeted ads? No.
How long does it keep your data? Proton does not store logs of your chats.