What does Prino encrypt?

Prino encrypts every chat, memory, project and file you keep, on your own device, before it is saved anywhere. The encryption uses AES-256, the same standard banks and governments use [2], through the encryption built into your browser [1]. The key that opens your data is created on your device and cannot be copied out of it.

That covers:

• your conversations, including titles and summaries
• the things Prino remembers about you
• your projects and their instructions
• files you attach or add to a project

Where is my data stored?

Your encrypted data lives in your browser's own storage on your device [3]. If you create an account, Prino also keeps an encrypted copy so your chats follow you to your other devices. That copy is scrambled with a key only your devices hold, so Prino's servers store data they cannot read.

Without an account, your chats stay in that one browser. Clearing the browser's site data deletes them for good.

What does the AI model see?

The AI model reads your message for a moment, because a model cannot answer text it cannot read. Prino only sends messages to models under zero data retention terms. The message is used to write the answer and is not stored afterwards.

This is the honest limit of any AI chat that runs in the cloud: encryption protects what is saved, while the model needs the words in front of it to reply. So Prino sends only what the answer needs, and nothing it receives is kept.

Is my data used to train AI?

No. Your chats, memories and files are never used to train AI, by Prino or by the models that answer you. Zero data retention goes further than a training opt-out: a message that is never stored cannot end up in a training set later.

Does Prino keep logs of my conversations?

No. Prino's service keeps only what it needs to run safely, such as counts, timings and error codes. It never logs your messages, the answers, your memories or your files.

Do I need an account?

No. You can open Prino and start chatting without signing up. An account is optional. It adds encrypted sync across your devices, and a password or passkey that unlocks your data on each one.

Is there a mode that saves nothing?

Yes. Ghost mode starts a chat that leaves nothing behind on your device: nothing is saved, nothing is remembered and nothing is synced. When you close it, it is gone.

What Prino does not promise

Private is not the same as anonymous. Prino keeps what you save unreadable to anyone but you, and makes sure what the model sees is not kept. It cannot make a message invisible to the model that answers it. If a detail isn't needed for the answer, leave it out.

How do you compare private AI chatbots?

Ask the same six questions of every product, because "private" means different things on different sites:

1. Do you need an account? An account links every chat to you.
2. Who can read your saved history? If the company holds the key, it can read your chats, and so can anyone who compels it.
3. Are your chats used for training? Training copies your words into a model.
4. Is your prompt deleted after the answer? A model has to read it to reply. Zero data retention means nothing is kept once the answer is written.
5. Does it remember you privately? Memory makes an assistant useful, but only if nobody else can read it.
6. Can you keep work in encrypted Projects? Projects group chats and files for one task, and should be as private as the chats themselves.

The comparison

Which should you pick?

Pick by the risk that matters to you:

• You want all six, in one place: Prino.
• You want to ask one thing without an account: Prino, Lumo guest mode, Duck.ai, Brave Leo or Venice.
• You want history and memory that nobody else can read: Prino, Confer or Lumo.
• You want nothing stored at all: Prino's Ghost mode, or Lumo guest chats, which are erased at the end of the session [3].
• You need prompts hidden even from the company running the model: look for a verified secure enclave, also called confidential computing. Confer offers one, and so does Venice on Pro.

What no private AI chatbot can promise

The model that answers you reads your message while it writes the reply. Encryption protects what is saved; zero data retention and secure enclaves limit what happens to the message after. Before you type something sensitive, leave out the details the answer doesn't need.

Why look for a private ChatGPT alternative?

Because ChatGPT is built to keep your chats. By default it saves every conversation until you delete it [2], may use chats to train OpenAI's models unless you opt out [1], and lets authorized staff review conversations in some cases [3]. Its encryption protects data in transit and on OpenAI's servers, but OpenAI holds the keys [4].

A private alternative changes who can read your words. Here is how to tell a real one from a marketing claim.

1. Can you start without an account?

A private alternative lets you ask a question without handing over an email address. Look for a guest mode or a "no sign-up" option, and check whether guest chats are saved and where.

2. Is your saved history end-to-end encrypted?

This is the big one. "Encrypted" alone usually means the company encrypts data with its own keys, so it can still read it. Look for end-to-end or zero-access encryption, where the key stays on your devices. Then the company stores data it cannot open.

3. Are your chats ever used for training?

The answer should be a plain no, with no opt-out needed. Watch for exceptions buried in the policy, such as feedback ratings or "de-identified" data still being used.

4. Who reads your prompt while the answer is written?

Every cloud AI model reads your prompt to answer it. Ask who runs that model and what they keep:

• Zero data retention: the model provider processes the message and doesn't store it.
• Secure enclave (TEE): the model runs in hardware that even the host can't look inside, which you can verify.
• "Anonymized": your identity is removed, but the provider may still keep the text for a while.

5. Does it remember you, privately?

Much of ChatGPT's usefulness comes from memory. A private alternative should offer memory too, encrypted like your history, so the assistant knows your context without the company knowing it.

6. Can you check the claims?

Read the privacy policy, not the homepage. Good signs are specific statements with numbers ("deleted within 30 days", "keys stored only on your device"), a clear list of who processes your data, and dated updates.

A quick scorecard

For side-by-side answers across Duck.ai, Lumo, Venice, Confer, Brave Leo and Prino, see the most private AI chatbots, compared. For how Prino answers each question, see how Prino keeps your chats private.

Does ChatGPT use your chats to train its models?

Yes, by default. For Free, Plus and Pro accounts, OpenAI says it may use your conversations to train its models [1]. You can turn this off in Settings, Data controls, Improve the model for everyone [2]. The switch only covers new chats.

One catch: rating an answer with a thumbs up or down can send that whole conversation for training, even after you opt out [1]. Business, Enterprise and Edu accounts are not used for training by default.

How long does ChatGPT keep your chats?

Until you delete them. Regular and archived chats stay saved to your account indefinitely [3]. When you delete a chat, OpenAI schedules it for permanent deletion within 30 days, unless it must keep it longer for security or legal reasons [3].

Can anyone at OpenAI read your conversations?

Yes, in limited cases. OpenAI says a small number of authorized staff and trusted service providers may access conversations to investigate abuse, provide support, handle legal matters, or improve models if you have not opted out [4]. OpenAI's own advice is not to enter sensitive information you would not want reviewed or used [4].

Is ChatGPT encrypted?

Partly. OpenAI encrypts your content in transit and at rest on its servers [5]. It is not end-to-end encrypted: OpenAI holds the keys, which is why staff can review chats and why a court can order them kept.

Can a court order OpenAI to keep deleted chats?

It has happened. In 2025, during The New York Times' lawsuit, a court ordered OpenAI to preserve ChatGPT conversations, including ones users had deleted [6]. OpenAI says that obligation ended on 26 September 2025, but data from that period is still held under legal hold [6] [7]. The lesson is general: anything a company can read, a court can ask for.

So, is ChatGPT safe to use?

For everyday questions, yes. For anything you would not want a company to store, review or hand over, it is not private by design. You can make it more private:

1. Turn off Improve the model for everyone.
2. Use Temporary Chat for one-off sensitive questions.
3. Delete chats you no longer need, and their saved memories.
4. Leave out names, numbers and details the answer doesn't need.

What does a private AI chat do differently?

A private AI chat encrypts your history on your device, so the company storing it cannot read it, and only sends your messages to models that don't keep or train on them. That is how Prino works: the model still reads each message to answer it, but nothing it sees is kept.

How do you delete one ChatGPT chat?

Open your chat history, click the ••• menu next to the chat, choose Delete and confirm [1]. A deleted chat cannot be restored. If you only want it out of sight, choose Archive instead, which hides it without deleting it.

How do you delete all your ChatGPT chats?

Go to Settings, then Data controls, then Delete all chats, and confirm [1]. This also deletes chats inside projects, and it cannot be undone.

How do you delete your ChatGPT account?

On the web, go to Settings, then Account, then Delete. Enter your email or phone number, type DELETE, and choose Permanently delete my account [4]. If you can't sign in, OpenAI's Privacy Portal accepts a deletion request instead. If you pay through Apple, cancel that subscription separately: deleting the account doesn't cancel it.

How long until deleted chats are really gone?

Up to 30 days. OpenAI schedules deleted chats for permanent deletion from its systems within 30 days [2], and deletes account data within 30 days of an account deletion [4]. Both have exceptions for security and legal obligations.

What does deleting a chat not remove?

Deleting a chat is not the same as deleting everything connected to it.

How do you stop ChatGPT remembering things?

Go to Settings, then Personalization, then Memory. You can delete single memories, turn off Reference chat history, or use Delete and turn off memory to clear the summary and stop new memories [3]. Turning Memory off does not delete your past chats, and OpenAI may keep logs of deleted memories for up to 30 days [3].

A quicker checklist

1. Delete the memories you don't want kept.
2. Delete the chats, one by one or all at once.
3. Delete files in your Library.
4. Turn off Improve the model for everyone so new chats aren't used for training.
5. If you're leaving, delete the account.

Is there a way to avoid this in the first place?

Yes: use an AI chat that never holds your history in readable form. In Prino, your chats and memories are encrypted on your device, so deleting them on your device deletes the only readable copy. Without an account, clearing your browser data removes them for good.

What is ChatGPT Temporary Chat?

Temporary Chat is a ChatGPT mode for a conversation that doesn't stick. It stays out of your chat history, doesn't create or update memories, and isn't used to train OpenAI's models [1]. OpenAI may still keep a copy for up to 30 days for safety reasons [2].

Does Temporary Chat use your memories?

It can. Before your first message you choose Personalized or Unpersonalized [1]. A Personalized temporary chat can read your existing memories, custom instructions and plugins, though it never adds new memories. An Unpersonalized one uses none of them. You can't switch once the chat starts.

What does incognito mode do?

Incognito mode only changes what your browser keeps on your device. Chrome doesn't save your history or site data from the session [3]. It does nothing to what websites receive: Google says the sites you visit may still see your activity, and signing in identifies you [3].

So ChatGPT in an incognito window works just like normal ChatGPT. If you're signed in, the chat is saved to your account, and if you haven't opted out, it can be used for training [4].

Temporary Chat vs incognito, side by side

What if you save a temporary chat?

It becomes a regular chat [1]. From then on it's kept in your history until you delete it, and follows the normal training setting.

Which should you use?

Use Temporary Chat when you don't want a conversation in your ChatGPT history or in training. Add incognito when you also don't want it in your browser history, for example on a shared computer. Neither stops OpenAI receiving what you type, and neither is end-to-end encrypted.

Is there a mode that keeps nothing at all?

Some private AI chats go further. In Prino, Ghost mode saves nothing on your device, remembers nothing and syncs nothing, and messages only go to models that don't keep them or train on them.