Gemini is safe for everyday use, but it is not private by default. Google saves your conversations to Gemini Apps Activity, keeps them for up to 18 months, and human reviewers can read sampled chats. Turning off Gemini Apps Activity stops long-term saving, though chats are still kept 72 hours for abuse handling.
Short answer
Gemini is safe for everyday use, but it is not private by default. Google saves your conversations to Gemini Apps Activity, keeps them for up to 18 months, and human reviewers can read sampled chats. Turning off Gemini Apps Activity stops long-term saving, though chats are still kept 72 hours for abuse handling.
Step by step
Open your activity settings: Go to myactivity.google.com/product/gemini. This is the real control panel, not the settings menu inside the Gemini app.
Decide on saving: Turn Gemini Apps Activity off to stop conversations being stored against your account. Leave it on if you want searchable history, and set auto-delete to 3 months instead of the default 18.
Assume review is possible: Google states that reviewers read a sample of conversations. Never paste anything into Gemini you would not be comfortable a stranger reading.
Export before you tighten anything: Turning activity off or shortening auto-delete removes history you may still want. Pull a Google Takeout archive of Gemini Apps first.
What "safe" actually means here
There are two separate questions hiding inside "is Gemini safe": is the output trustworthy, and is the input private. They have different answers.
On output, Gemini is a language model. It is confidently wrong often enough that anything factual, legal, medical, or financial needs checking against a real source. That is a limitation, not a safety flaw.
On input, the honest answer is that Gemini is less private than most people assume.
What Google keeps
When Gemini Apps Activity is on, Google saves your prompts, Gemini's responses, uploaded files, and related usage data. The default retention is 18 months, and you can change it to 3 or 36 months, or off.
Two details catch people out:
Human review. Google says reviewers read and annotate a sample of conversations, and reviewed conversations can be kept up to three years, separately from your activity settings.
The 72 hour window. Even with activity off, Google retains conversations for up to 72 hours to run the service and handle abuse reports.
Where Gemini is genuinely risky
Workspace accounts behave differently from personal ones, and enterprise Gemini has its own data commitments, but on a personal account you should treat Gemini like a public forum with a very small audience. Do not paste client data, patient details, unreleased financials, passwords, or anything covered by an NDA.
What to do instead
Use Gemini for drafting, structuring, explaining, and brainstorming. Redact identifiers before pasting anything real. Then export periodically so the useful conversations live in your own files rather than in an account whose retention window is quietly ticking down.
Frequently asked questions
Does Google train on my Gemini chats?
Conversations that are saved to Gemini Apps Activity can be used to improve Google's services, including via human review. Turning the activity setting off stops that use for future chats.
Can other people see my Gemini conversations?
Not other users. Google reviewers can read sampled conversations, and anyone with access to your Google account can read your history.
How long does Google keep Gemini chats?
18 months by default, adjustable to 3 or 36 months. Reviewed conversations can be kept up to three years.
Is Gemini safe for work documents?
On a personal account, no. Use an enterprise or Workspace tier with data protection commitments, or redact before pasting.