Prompto is an open-source web application intended to simplify and enhance the way users interact with large language models (LLMs). Its effortless switching between different LLMs ensures that users have the tools they need for varied language processing tasks. Prompto aims to provide a seamless, secure, and user-friendly experience, ensuring that users can leverage the power of LLMs without the associated complexity. Its design focuses on maintaining user preferences and conversation history locally, avoiding the need for server storage and enhancing user privacy and security.