04-x is a privacy-first chat platform for working with modern LLMs in a familiar chat interface, without giving up control of your data.
Privacy and end-to-end encryption
Your data is encrypted end to end using a password you set. This includes:
- API keys
- Prompts
- Model responses
Only you can access your chat history and settings. The platform cannot read your sessions and does not use them to train models.
Supported models
04-x supports popular models from OpenAI and Anthropic, so you can test and compare outputs in one place:
- OpenAI: GPT-4, GPT-4o mini, GPT-3.5, DALL·E 3
- Anthropic: Claude 3.5 Sonnet, Claude 3 Opus, Claude 3 Haiku, and others
Web app experience
You can sign in with Google or email. The interface includes demo chats and example dialogues (e.g., algorithms, language practice, system actions) to help you get started quickly. 04-x is a fit for developers, advanced users, and anyone who wants to use powerful LLMs while keeping their data private.

