Jan

Jan is an open-source desktop AI chat app for individuals who want a privacy-focused ChatGPT alternative that can run fully offline on Windows, macOS, and Linux.

Key capabilities include:

• Run local LLMs offline by downloading open models (for example Llama 3, Gemma, Mistral) from Hugging Face or importing GGUF models
• Connect to cloud AI providers (including OpenAI, Anthropic, Groq, and others) using API keys when local inference is not required
• Use a chat UI with model parameter controls and session context, plus real-time web search
• Expose an OpenAI-compatible local API (localhost:1337) powered by the Cortex engine, designed for integration with other tools (for example Continue.dev)

Pricing: Free (open-source). Model and cloud usage costs depend on local hardware and any third-party API billing.

What makes it notable: it supports 100% offline operation after setup, targets air-gapped and high-security environments, and avoids data telemetry and internet dependency while still offering optional cloud model connectivity.