Gemini can train on your chats, paid or not. Here's the 3-step check.
A post called "Tell HN: Gemini trains on chat history, even for subscribers (personal accounts)" went past 600 points on Hacker News on November 4. The author, jameslk, said they had not realised that paying for a Google AI plan does not stop their chats being used for training.
I did not want to repeat the headline, so I read the thing it points at. This is Google's Gemini Apps Privacy Hub, last updated October 26, 2026. Here is what it actually says, and what it does not say.
What Google's page says
With the Keep Activity setting on, Google says it uses your activity "to provide, develop, and improve its services (including training generative AI models)". That is on the Privacy Hub page for Gemini Apps (support.google.com/gemini/answer/13594961).
Two details matter if you build things for a living.
First, the page does not list an exception for paid personal plans. It mentions "a paid subscription to a Google AI plan" only as information Google collects, not as a reason your chats are treated differently. So the Hacker News reading is fair. It is also only a reading of what the page leaves out, so if Google has a separate paid-plan term somewhere else, I did not find it.
Second, work and school accounts are different. Google says use of Gemini Apps with those accounts "may be subject to different data handling terms" and points to its Workspace privacy hub. If you pay for Workspace, you are not in the same bucket as someone on a personal plan.
The part about people reading your chats
The same page says a subset of chats is reviewed by human reviewers, including Google's trained service providers. Google says chats are disconnected from your account before they are sent to those providers. It also says reviewed chats are retained for up to three years, and that they are not deleted when you delete your activity.
Read that last part twice. Deleting your Gemini activity does not delete a chat a reviewer has already seen.
Google's own advice on the page is blunt. If Keep Activity is on, "don't enter data that's confidential or that you wouldn't want a reviewer to see or Google to use to improve its services."
By default your saved activity is auto-deleted after 18 months. You can change that to 3 or 36 months, or choose not to auto-delete.
What the off switch does
Turn Keep Activity off and Google says your future chats won't appear in your Activity and won't be used to train its AI models, unless you send feedback. Temporary chats are described the same way: not used to train Google's AI models.
There are three catches the page spells out:
- Chats you have with Keep Activity off, and temporary chats, are still kept with your account for 72 hours. Google says this is so Gemini can respond, process feedback and protect Google and its users.
- Even with Keep Activity off or in a temporary chat, Google says it still uses your chats "to respond to you and help protect Google, our users, and the public, including with help from human reviewers." So the off switch stops training and review for improvement. It does not promise nobody can ever see a chat.
- Some features need it on. The page says some Connected Apps, such as Google Workspace, are unavailable when Keep Activity is off. Commenters on the Hacker News thread also said some Pixel assistant features stop working. I have not tested that, so treat it as a report.
What the Hacker News thread got wrong, and right
Right: the claim that paying does not switch training off for a personal account matches what the page says.
Overstated: a few comments suggest every chat is read by a person. Google says "a subset". It does not say how big that subset is, and the author of the post made the same point, that "subset" is undefined. So the honest summary is that some chats are read, you cannot tell which, and the copies stay for up to three years.
Also worth keeping in mind: several commenters said other AI providers review some chats too, and that is a claim, not something I checked for each one. This post is only about what Google's page says.
If you build with the API, it is a different deal
Google's Gemini API terms (effective March 23, 2026) split services into two kinds.
Unpaid services, which include Google AI Studio and unpaid Gemini API quota: Google says it uses the content you submit and the responses to "provide, improve, and develop" its products, and that human reviewers may read, annotate and process your API input and output. It tells you not to submit sensitive, confidential or personal information.
Paid services, which include paid Gemini API quota: Google says it doesn't use your prompts or responses to improve its products. It logs them for a limited period, solely to detect and prevent violations. The page does not mention human review for paid services.
So if you are pasting client code into the free tier because it is convenient, that is the one worth fixing first.
The 3-step check
- Open Gemini and find Keep Activity. Turn it off, or use temporary chats for anything work-related. Remember that off means a 72-hour copy still exists.
- While Keep Activity is on, treat every chat as readable. No API keys, no client code, no contracts, no customer data. Google's page says this itself.
- If you build on the Gemini API, check which quota you are on. Free quota and AI Studio can be used to improve Google's products. Paid quota is not.
What to do this week
Set a reminder for 10 minutes. Open Gemini settings, look at Keep Activity and your auto-delete period, and decide on purpose instead of by default. Then look at where your team pastes code. If any of it goes into a free tier or a personal account, move it to paid API quota or a work account that has its own terms.
I am not saying Gemini is worse than anything else. I am saying the setting has a cost and the paid plan does not remove it, and most people find that out from a Hacker News thread instead of a settings page.
Sources
- Google, Gemini Apps Privacy Hub (last updated October 26, 2026): https://support.google.com/gemini/answer/13594961
- Google, Gemini Apps activity: https://support.google.com/gemini/answer/16836988
- Google, Gemini API Additional Terms of Service (effective March 23, 2026): https://aistudio.google.com/docs/terms
- Hacker News, "Tell HN: Gemini trains on chat history, even for subscribers (personal accounts)": https://news.ycombinator.com/item?id=50363461
- AI Weekly, "Google Gemini trains on paid subscribers' chats by default" (November 4, 2026): https://aiweekly.co/alerts/google-gemini-trains-on-paid-subscribers-chats-by-default
Which of these did you already have switched off?