Best private AI chatbots

Side by side

Our picks in detail

Checked 27 October 2026 against Proton, DuckDuckGo, Brave, Venice, Confer, Privatemode, Apple, OpenAI, Anthropic, Ollama, LM Studio and Jan privacy pages, help articles and pricing pages.

Our pick

Proton Lumo is my pick for most people because it pairs a free plan with the strongest documented no-log promise among cloud chatbots. Proton's Lumo privacy article says it keeps no logs of your chats, stores saved history with zero-access encryption and does not train on conversations. Lumo Free needs no account to start, and Lumo Plus is the paid tier, priced in the ranking table below. The trade-off: your prompt still reaches Proton's servers, so only a local app keeps it on your device.

Which AI is 100% private?

No cloud chatbot is 100% private. Every cloud service receives your prompt in readable form at some point, or relies on special hardware and contracts to stop anyone reading it. The honest answer to "which AI is completely private?" is a local model.

• Local models run on your laptop or desktop. The prompt, the reply and the history stay on your disk. Nobody else can log them, because they never travel.
• Encrypted cloud chat narrows who can see your data. Venice's E2EE mode, Confer and Privatemode encrypt a prompt on your device and decrypt it only inside a verified secure enclave.
• No-log cloud chat depends on the company keeping its promise. Lumo, Duck.ai and Brave Leo fall here.

My guide to open-weight vs closed models explains which models you can download and run yourself.

Which AI is most private?

Ranked on what each vendor documents about logging, training, retention, encryption and sign-up, a local app is the most private option, and Proton Lumo is the most private cloud chatbot with a free plan. This table sets the seven picks side by side on price, sign-up and training.

What is private AI?

Private AI means an assistant that limits who can see, keep or learn from your conversations. Vendors use the phrase for four different things, so check which one you are getting:

1. No training: your chats are not used to improve the model. ChatGPT, Claude and Gemini offer this as a setting; private tools make it the default.
2. No logs or short retention: the company deletes prompts after answering, or within a set period.
3. Encryption the vendor cannot read: zero-access storage, end-to-end encryption or confidential computing.
4. Local processing: nothing leaves your device at all.

Only the fourth removes the need to trust anyone. My AI tool privacy checklist lists the settings to check on any assistant.

Private ChatGPT options

If you want to stay on ChatGPT or Claude, both offer a more private mode, but neither is anonymous.

• ChatGPT Temporary Chat: OpenAI's Temporary Chat article says temporary chats are not used to improve its models and do not create memories. OpenAI may keep a copy for up to 30 days for safety purposes.
• Claude incognito chats: Anthropic's incognito chat article says incognito chats are not used to improve Claude, even if model improvement is on, and are not added to memory. They are kept for 30 days by default, or longer under an Enterprise organization's custom retention setting.

Both modes still tie the chat to your account. For the full feature comparison, see my ChatGPT review and Claude review, or the ChatGPT alternatives ranking.

Anonymous and incognito AI chat

"Anonymous AI" and "incognito AI" mean the service cannot link a chat to you. Three picks do this without an account:

• Duck.ai removes your IP address before the provider sees the request.
• Brave Leo needs no account, and Brave says it collects no identifiers linked to you.
• Proton Lumo Free lets you start chatting without creating a Proton account.

Anonymous is not the same as confidential. If you paste your name, address or a client file into the prompt, the text itself identifies you. Duck.ai's own policy warns that personal information in a prompt may be reproduced in the output.

For plans, model choices and how its privacy claims hold up, read my Venice AI review.

For Duck.ai's models, limits and chat storage in detail, read my Duck.ai review.

Best free private AI

• Free and fully private: LM Studio, Ollama or Jan running a local model.
• Free in the cloud, most documented protections: Proton Lumo Free.
• Free with no account and big-name models: Duck.ai, within its daily limit.
• Free inside the browser: Brave Leo.
• Free with a privacy-mode choice: Venice Free, limited to 10 text prompts a day on 27 October 2026.

Free plans cap usage, so heavy users end up on a paid tier or a local model. My list of free AI tools covers free plans beyond privacy.

Private AI apps and assistants

Phones and computers now ship assistants with their own privacy designs.

• Apple Intelligence runs many requests on device. For larger requests, Apple's Private Cloud Compute post, published 10 June 2024, says personal data is used only to fulfil the request, is not retained, and that Apple's staff have no privileged runtime access. Apple also commits to letting security researchers verify those claims.
• Lumo, Duck.ai and Brave Leo have mobile apps or work in mobile browsers.
• Local apps such as LM Studio, Ollama and Jan run on desktop computers rather than phones.

For a closer look at one of the encrypted chat options ranked here, see my Confer review.

Are AI chats private?

By default, mainstream AI chats are not fully private. Most assistants store your history on their servers, and several use conversations to improve models unless you opt out. Employees or contractors may review flagged chats for safety. A chat can also be disclosed under a legal order.

What you can do:

1. Turn off model training in your settings.
2. Use a temporary or incognito chat for one-off sensitive questions.
3. Delete old conversations you no longer need.
4. Keep confidential data out of cloud chat altogether, or use a local model.

My AI chatbot rankings list each major chatbot's training and retention settings.

Going fully local

Running AI locally is the only way to make a chatbot 100% private. The basic steps:

1. Install an app: LM Studio, Ollama or Jan.
2. Download an open model that fits your memory. Smaller models run on a laptop; larger ones need a strong GPU or a Mac with plenty of unified memory.
3. Disconnect and test. Once the model is downloaded, it works offline.
4. Check optional cloud features. Ollama and LM Studio both offer cloud models, which are not local. Leave them off if you want everything on your machine.

The trade-off is capability. The most capable models on public leaderboards are closed models you cannot download, so a local setup suits private drafting, summarizing and coding help more than the hardest reasoning tasks. My AI models comparison shows how closed and open models compare.

For step by step setup with apps like Ollama and LM Studio, see my guide to running AI locally.

To pick which open model to run, my best local LLMs list covers picks for coding, writing and hardware.

How we ranked

I read each vendor's privacy policy, privacy article, help pages and pricing page on 27 October 2026. I ranked on five documented factors: whether chats are logged, whether they train models, how long they are kept, whether the vendor can read them, and whether an account is required. Every privacy claim here is stated as the vendor publishes it. Products whose main pitch is removing safety rules are out of scope. The full method is on the HumanRank ranking methodology page, and more rankings sit in the best AI tools hub.

Questions people ask