Which AI doesn't train on your chats? We checked 9 (October 2026)
Short answer: most do, unless you switch it off. Of 9 popular AIs, 5 train on what you type by default on a free personal account (ChatGPT, Perplexity, Mistral, DeepSeek, Meta AI). Two depend on a setting (Gemini and Claude), NotebookLM says it doesn't unless you send feedback, and Microsoft's new Copilot app doesn't say. Switching training off helps, but it doesn't make a chat private: feedback, human review and data already used still count. The only way nothing leaves your computer is an AI that runs on it.
What each one says (checked 18 October 2026)
We read each company's own help pages, for a free personal account, and link them here. Work and school accounts usually have stricter rules: they're left out of training by default on most of these services. Policies change often, so we check again every month.
| AI | Trains on your chats? | How to turn it off | What the switch doesn't cover |
|---|---|---|---|
| ChatGPT (Free, Go, Plus, Pro) | Yes, by default | Settings → Data controls → "Improve the model for everyone" off. Temporary Chats aren't used. | Thumbs up or down feedback: the whole conversation may be used. OpenAI |
| Gemini | Yes, while "Keep Activity" is on | Turn off Keep Activity. Future chats aren't used to train, but are still kept 72 hours. | Chats a human reviewer has read are kept up to 3 years, even if you delete your activity. Google |
| Claude (Free, Pro, Max) | Only if you allow it (you choose when you sign up) | Privacy settings → model improvement off. | If allowed, chats are kept up to 5 years; turning it off later doesn't remove data already used. Anthropic |
| NotebookLM (Gemini Notebook) | No, unless you send feedback | Nothing to switch off. Don't use thumbs up or down on sensitive notes. | With feedback, your uploads and questions can be reviewed and kept up to 3 years. Google |
| Microsoft Copilot (new app since 18 Aug 2026) | Not stated for the new app | Microsoft's training opt-out is described only for the old app. The new app's privacy controls list no training switch. | Check the app's own settings. Microsoft |
| Perplexity (Free, Pro, Max) | Yes, by default | Settings → Preferences → "AI data retention" off. | Only stops data from then on; earlier data isn't removed. Perplexity |
| Mistral Le Chat (free) | Yes, by default | Settings → Privacy → "Allow your interactions to be used to train our models" off. | Thumbs up or down feedback is used whatever you choose. Mistral |
| DeepSeek | Yes, by default (de-identified) | Turn off "Improve the model for everyone". | DeepSeek |
| Meta AI | Yes: your questions to Meta AI are used | In the EU, object with Meta's form (from the app or the email Meta sent). | The objection covers the account you're logged into and others in the same Accounts Centre. Meta |
| GreenCube (runs on your PC) | No: your chats never reach us | Nothing to switch off. | Online search, which starts off every time, sends search terms to search engines. GreenCube |
What "turn off training" doesn't do
1. Feedback still counts
Clicking thumbs up or down often sends the whole conversation for review, even with training off. OpenAI, Mistral and Google (NotebookLM, Gemini) all say so. If a chat holds something sensitive, don't rate it.
2. Humans may read some chats
Gemini uses human reviewers while Keep Activity is on, and keeps reviewed chats up to 3 years, disconnected from your account, even if you delete your activity.
3. What's already used stays used
Turning training off only affects what you send from then on. Anthropic and Perplexity both say data already in training isn't removed. If you're going to switch it off, do it before you paste in your notes, not after.
The only way nothing leaves your computer
Every service above runs the AI on its own servers, so what you type has to travel there, whatever the training setting says. An AI that runs on your own computer works the other way round: the model is a file on your PC, your chats and documents are stored there, and there is no company server holding them.
That's how GreenCube works. Its privacy policy says it plainly: "We never receive your chats, files, memories or images." The honest exceptions: you sign in once to activate it, it downloads the AI and its updates, and if you switch on Online search for something current, it sends search terms built from your question to search engines. Online starts off every time you open the app.
The trade-off is your computer does the work. On the PCs we measured, it writes from about reading speed on an 8 GB laptop to many times faster on a gaming PC. Check what yours can run.
How we checked
On 18 October 2026 we read each company's own help center and privacy pages for a free, personal, adult account, not news articles or reviews, and linked the page each row comes from. Where a company's current pages don't answer the question, as with Microsoft's new Copilot app, we say so instead of guessing. We'll check again every month and update the date at the top.
Questions
Does ChatGPT train on my chats?
On Free, Go, Plus and Pro, yes by default. You can turn off "Improve the model for everyone" in Settings, Data controls. If you give thumbs up or down feedback, OpenAI may still use that whole conversation.
Which AI doesn't use my data for training?
Of the 9 we checked, NotebookLM says it doesn't train on your uploads unless you send feedback, and Claude only does if you allow it. An AI that runs on your own computer, like GreenCube, never sends your chats to anyone to train on.
Does turning off training make an AI private?
Not completely. Feedback you give can still be used, some companies keep chats for human review (Gemini keeps reviewed chats up to 3 years), and data already used in training isn't removed.
Is there an AI that keeps my chats on my computer?
Yes: an AI that runs locally, like GreenCube, keeps chats and files on your PC. Its only online part is an optional web search that sends search terms, and it starts off every time.
Your own AI, on your own PC
GreenCube runs on your computer: no usage limits, no subscription, works without internet. €9.99, paid once.
Get GreenCube