AI chat apps that work without an account

Facts from each product's own page or US App Store listing, checked November 8, 2026. Links are in the sources below.

Duck.ai: free, anonymous access to several models

DuckDuckGo says Duck.ai and Search Assist "are free to use and anonymized by us, with no account required" (DuckDuckGo help). DuckDuckGo calls the model providers on your behalf, so they don't see your IP address, and its agreements with them rule out training on your prompts (Duck.ai privacy policy). If you want the strongest cloud models with no sign-up, this is the easiest place to start. Your prompts are still processed by those providers' servers.

ChatGPT without logging in

OpenAI says ChatGPT "can be accessed before creating an account at chatgpt.com". While logged out, "you can only have one conversation at a time", and chats "remain accessible only for the current session on the same browser." OpenAI also says that "whether chats are used to train our models by default depends on your location and settings". You can turn off "Improve the model for everyone", but logged out, that setting is saved only in your browser (OpenAI Help).

Lumo guest access

Proton says you can "use guest access for anonymous AI chat — with no need to log in or create a Proton account", and that Lumo Plus adds unlimited chats (proton.me/lumo). Lumo's free plan has limited messages and chat history.

On-device apps: no account because there's no server

When the model runs on your phone, there's often no reason for an account at all. Sema has none: chats and memories stay on the iPhone, and only anonymous analytics plus optional, consent-first web search leave it (privacy policy). The PocketPal AI and Private LLM listings describe downloading a model and chatting offline, with no sign-up step mentioned, and both list "Data Not Collected" (PocketPal AI, Private LLM). The catch is that phone-sized models are less capable than the cloud ones above.