Jan

Jan is an open-source alternative to ChatGPT that runs open-source AI models entirely offline on your computer, or connects to cloud models like GPT and Claude when you want them. Built on the llama.cpp engine, it supports popular models like Llama, Mistral, Qwen, and DeepSeek with local inference. Key features include LocalDocs for augmenting chats with your own files (data never leaves your machine), custom assistants with specialized system prompts, an OpenAI-compatible API at localhost:1337 for app integration, and Model Context Protocol support for agentic capabilities. Available on Windows, macOS, and Linux under the AGPLv3 license. For developers who want an open-source, privacy-first chat interface that works with both local and cloud models, Jan bridges both worlds cleanly.